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How hot is a volcano? Where do we get salt from? How does my Nintendo Wii work? Ever wanted to know a question about science, technology or gadgets but were too afraid to ask?! Well, here at Scipod Online, we've got a team of experts all lined up and ready to answer almost anything you can think of. Just type in your question below and we’ll post the most interesting ones (along with our answers, of course) on this page. Don't forget to include your name so we know who's asking!
When an object feels hot, the atoms that make up the object are moving around fast. When it feels cold, the atoms are moving slower.
Some atoms are moving faster than others in the object, but their average speed always remains the same, and so temperatures is a way of describing the range of speeds of the atoms all together.
The usual way we measure temperature is using the Celsius scale, but there is another scale called the Kelvin scale, which is based on theory, rather than experiments.
On the Kelvin scale, the zero point (0K)is the same as -273.15 degrees Celsius.
As the temperature of an object drops, the speed of the atoms slows down, until at 0K (or -273.15 degrees Celsius), the atoms all stop moving.
So, it is impossible to get colder than this temperature. This is called Absolute Zero.
The coldest place in nature, is in outer space where it is 3K, just three degrees above Absolute Zero (0K), though in laboratories, scientists have cooled objects down to 1/1000th of a degree above 0K.
The average distance between the Sun and the Earth is about 92,935,700 miles.
The actual distance between the Earth and the Sun changes slightly over the course of the year. This is because orbit of the Earth around the Sun is not a perfect circle.
Astronomers refer to this distance as one astronomical unit (AU), the distance that light travels in about eight and a half minutes.
Unlike the Nintendo’s Wii, which uses a controller to track player’s movement (see previous answer below), the Xbox 360 uses Kinect, which can track your movement across a room, without using any hand-held controllers.
It can do this by using an infrared laser which is scanned across the room (the laser measures infrared part of the spectrum of light, that is, a part of light which our eyes can’t see). The laser works out which parts of the view are far away and which are near. This is called a ‘depth field’.
Once this hardware has all the information, there is some software which takes the image and works out which part of the image is the player and which is the room. It bases this on the fact that most people are of a certain size range and have two arms and legs. All the other joints of the skeleton are guessed and filled in, so the Xbox has a complete picture of the player and their movements and position.
A few readers have emailed in their questions about how salt is made.
Salt is found mostly underground in rocks and also dissolved in sea water. To get the salt from the sea, you have to collect sea water in shallow ponds and let the wind and sun dry out the water naturally, leaving only the salt behind. This is called solar evaporation, and the salt can form in layers up to 30 cm thick.
However, as the concentration of salt in the sea is about 3%, a great deal of energy is needed to produce dry salt, and it is only feasible in hot, dry areas.
In northern regions, salt is usually produced from solid deposits of rock salt. These deposits were formed from the evaporation of shallow seas in hot, dry climate, around 200 million years ago and occur in many regions of the world. In the North of England we have deposits in mid-Cheshire (in Northwich and Winsford).
The extraction process involves injecting hot water into these underground deposits of salt, which dissolves the salt, and the resulting concentrated solution (brine) is pumped out. The saturated brine (26% NaCl or sodium chloride) is then boiled in large vessels called effects.
Steam is used to heat the brine in chambers called calandrias. To save energy, there are lots of chambers linked together at different pressures. As the boiling point of water decreases with decreasing pressure, you only need to heat the first chamber, and the steam from the first will heat the second chamber, and so on.
This means that the final evaporation chamber is under vacuum. For this reason, the salt made in this process is called vacuum salt. This is what happens at the INEOS salt plant in Runcorn.
The first product of the evaporation process is a mixture of salt in brine. This is then centrifuged (spun round very fast) to give a slightly damp salt called Undried Vacuum Salt which is largely used by the chemical and water treatment industries.
Some of this salt is further dried to give Pure Dried Vacuum Salt (PDV). This product is used for industrial water softening, the cosmetics industry, food and many other applications.
Did you know?
The word “salary” comes from the Roman times, when soldiers were given money to buy salt!
(Question submitted by Connor)
Oil, coal and gas are all called ‘fossil fuels’, which means they are made from the decay of ancient organisms that lived millions of years ago. The organic matter has been squashed beneath layers of rock and turned into coal reserves, with oil and gas being produced from the same process and trapped by overlying rocks.
Also, the Earth’s crust is full of metal deposits (aluminium is the most common metal in the crust), but these have also taken millions of years to form.
People are trying to explore other ways of making energy, instead of burning fossil fuels. Nuclear, wind, hydro-, solar and tidal are all alternative ways of producing electricity (called renewable energy sources, as they don’t run out).
Also, by recycling metals, instead of throwing them away, we can reduce the amount of mining new metals from the Earth.
When an object is hotter than its surroundings, then a process called heat transfer happens. This is when heat (or thermal energy) flows from the hotter object to the cooler one, for example a cup of tea cooling down on a table.
Some of the heat will be lost to the table through conduction (through direct contact with eachother), while some will be lost through convection (in the steam rising up from the cup). The rest of the heat will be lost through radiation (heat transfer through empty space), or the sides of the cup being in contact with the cooler air.
Heat transfer will only happen when there is a difference in temperature. When the two objects are at the same temperature (for example the cup and the table, or the cup and the air), the transfer stops and is said to be in equilibrium (meaning in the same state). This is why a hot object in room temperature can't cool down further than the temperature of the room.
When you hold a piece of magnesium ribbon over a lit Bunsen burner, the magnesium reacts with the oxygen in the air and forms magnesium oxide.
The chemical reaction for this is 2Mg + O2 = 2MgO.
This reaction is an exothermic reaction which means there is a net release of energy (in this case, in the form of heat and light).
The reaction produces an intense, bright, white light when it burns.
Because of this, uses of magnesium include flash photography, emergency flares and fireworks sparklers.
Watch the experiment at:
http://jchemed.chem.wisc.edu/JCESoft/CCA/CCA3/MVHTM/MAGAIR/MAGAIR.HTM
WARNING - do not try to do this experiment yourself. If watching a teacher demonstrate this, do not look directly at the white light produced as it could damage your eyes.
Challenger Deep in the Marianas Trench is the deepest place in the ocean at nearly 11 kilometres. The trench formed because when tectonic plates (pieces of the Earth’s crust that fit together like a jigsaw) meet each other, one is sometimes bent underneath the other, and the boundary forms a long deep trench under the oceans. We know the exact depth because scientists sent down a submersible (a type of submarine made for really deep journeys) right to the very bottom.
Did you know?
If you were standing at the bottom of the ocean in Challenger Deep, the pressure of all the water would feel like 50 jumbo jets on top of your head!
(Question submitted by Jacqui)
The Earth is like a big bar magnet with a North and a South Pole. These are near to the real poles but not exactly in the same place. There isn’t a real bar magnet in the Earth though. Liquid metal in the centre of the Earth’s core (liquid because it’s so hot down there) moves around as the Earth rotates and generates electricity and magnetism just like an electric generator does.
The tip of a compass needle is magnetised so it is attracted to the magnetic North pole of the Earth. The magnetic field of the Earth is quite weak at the surface, so any strong magnetic near the compass will change its direction.
Did you know?
The North and South magnetic poles sometimes change places! The last time this happened was 780,000 thousand years ago.
The short answer is very hot! The temperature of a volcano depends on what you measure. If you measure the temperature of the gases that can come out of the ground by a volcano, these can be high enough to boil water. Chunks of rock that have been blasted out the top of a volcano (called pyroclastic deposits – from the latin ‘pyro’ meaning fire and greek ‘clast’ meaning broken) can be as hot as 200°C.
If you measure the lava (hot melted rock) that flows out of a volcano, then this can be anything from 700°C to 1200°C. Compare that to the hottest setting of 240°C in your oven at home!
Did you know?
One in 10 people live in the danger zone of an active volcano!
(Question submitted by Jess)
The simple answer is that if you mixed them at room temperature not a lot would happen. You would have to have very high temps for a reaction. Beryllium Chloride is a compound which is slightly unusual compared to similar group 2 compounds so I suggest this link which gives a little more detail:
http://www.chemguide.co.uk/inorganic/group2/beryllium.html
Also have a look at the 118 videos from Professor Poliakoff on each element in the periodic table at: www.periodicvideos.com
(Answered by Sue Halliday - Catalyst Science Discovery Centre)
(Question submitted by Craig)
This is a great question as the answer isn’t as straightforward as you think. Not only are there loads of different ways to measure how big something is, the size of the Sun will be different in the future than it is now! Read on…
Here are three ways of measuring how big a sphere is (the shape of the Sun is called a sphere):-
Diameter – this is the measurement from the two furthest points on the surface of a sphere, passing through its centre (for example the distance between the North and South pole on Earth right through the middle). The diameter of the Sun is 1.4 million kilometres, or to put it in perspective, 109 times bigger than that of Earth!
Surface area – this is how much exposed area a solid object has. For the Sun, this is 6.0877×10^18 square metres, or put more simply, 6,087,700,000,000,000,000 square metres! That’s 11,990 times larger than the Earth!
Volume - the amount of space an object takes up - shows just how big the Sun is. The volume of the Sun is estimated at 1.412×10^27 cubic metres, or 141,200,000,000,000,000,000,000,000 cubic metres! To compare this with our planet, you could fit 1.3 million Earths inside the Sun!
The life-cycle of the Sun
The Sun is about half-way through its life, and is thought to be around 4.5 billion years old. In about 5 billion years, the Sun will become a red giant star which will be about 400 times bigger (in diameter) than it is at the moment. This is because all the hydrogen that is being burnt up in the Sun’s shrinking core will make its hot outer gases expand. After this, the Sun will cool down and become a much smaller white dwarf, which is made up of the remains of the core of the star.
Find out more at: http://www.bbc.co.uk/science/space/
(Question submitted by Lamese, Ciara and Alice)
When you say ‘burn’ I suspect you mean ‘combust’ (set on fire). Combustion is a chemical process that requires a fuel and some oxygen. Most ‘fuels’ that are burnt in this way are or used to be alive – wood and paper come from trees for example.
Living and ex-living things store up the energy they originally got from sunlight and then let it go when they burn. Most rocks originally came from deep inside the Earth and were never alive – they can’t be ‘burnt’ because they don’t have this type of energy available for release. An important exception is coal which is a rock and which can be burnt very easily. In fact, it is burnt everyday in power stations all over the world and the energy this burning releases provides much of the electricity we use.
Why does coal burn when other rocks don’t? The answer is that it was once alive – coal is a rock made up of the remains of plants and other living things which died, in most cases, hundreds of millions of years ago.
The word ‘burn’ can also be used in a broader sense to describe the alteration of something by a lot of heat. Think of how toast ‘burns’ (becomes hard and black) without having to catch fire if you accidentally leave it in the toaster for too long. Most rocks will start to melt into liquid at about 1,000 degrees Celsius but even well below this temperature, they can change colour and hardness just like toast. Geologists sometimes refer to rocks that have been altered by heat in nature (from a nearby volcano for example) as ‘burnt rocks’.
(Answered by Dr. Andy Biggin - Geophysicist at University of Liverpool)
(Question submitted by Priyanka Lad)
Coal is a rock which is formed from the dead remains of plants that have been buried over many years under water. Over time, the plant matter becomes squashed and buried under sand and other rock and in the end turns to coal. The coal traps carbon from the atmosphere from when the plants were alive.
When you burn a lump of coal in air, the carbon it contains joins with the oxygen in the air and forms a gas called carbon dioxide. People burn coal to heat their fires and also to generate electricity through the use of burning the coal in an oven which heats a boiler to produce steam and drive steam turbines which can generate electricity.
If you burn coal in an enclosed space, there is not enough oxygen to make carbon dioxide and so another gas called carbon monoxide is formed, which can be dangerous to humans and animals.
If you want to know more about Carbon and Oxygen, why not visit the Video Periodic Table at http://www.periodicvideos.com/ ?
Electricity is a form of energy that comes from tiny charged particles in an atom (called electrons) which flow around in a path. This movement is called an electric current, and although we can’t see this, we can see the effects it makes, like powering a light bulb or phone.
Electricity can be made by using generators, which change one type of energy into electricity. For example, by changing water power into electricity using a hydro-electric power station, or by burning coal or oil to heat water (the steam drives the generators to make electricity).
Another good example of electricity generation is wind power. The wind causes the propellers of a wind turbine to move and this movement in changed into electricity.
The Future Flower at Widnes uses wind energy to power the red lights on its petals!
(Question submitted by Kendal)
The Earth is made up of layers (a bit like an onion), with a thin crust on the outside, then a semi-solid mantle and then the core. The outer part of the core is liquid, because of the hot temperatures that keep the material molten. The inner part of the core is solid because at that depth, the pressure of all the rocks above is so great.
The source of the heat in the earth is thought to come mostly from the radioactive elements in the mantle (the layer between the core and the crust), but some heat comes from what was already there when the Earth formed (the crust that formed kept in the heat, like a blanket).
We can’t measure the temperature at the core directly, but because we think it is made mostly of iron, we can do experiments to compare how other materials behave at different temperatures and pressures, and guess at what temperatures iron melts at the same pressures as the core. The answer could be somewhere between 4000 and 7000 degrees C, but nobody really knows yet.
The Earth is cooling all the time, and as it does the liquid outer core freezes and a little bit more becomes solid. One day, the Earth will cool down completely, like the Moon has already.
See the other questions about the Earth further down the page!
Carbon Monoxide (CO) can be formed when there is not enough oxygen in the atmosphere to form Carbon Dioxde when organic matter like oil or coal is burned. For example, this could be from a oven or heater in the home where there is not enough ventilation (free flowing air) around.
CO can join up with haemaglobin (the protein in our blood which helps to carry oxygen around our bodies) and make a new compound. This means that oxygen can no longe combine with the haemaglobin and parts of the body are starved of oxygen.
Low levels of CO can cause headaches, dizzyness and short of breath, but higher levels could cause memory-loss, heart problems and even death.
Because we can't see, smell or taste CO, it is best to have a detector put near any machines that may produce CO and warn us when levels are too high.
Since 1930, everyone thought that Pluto was the furthest planet from the Sun in the Solar System.
However, in 2006, another small object called 2060 Chiron was found in the outer Solar System and then many more similar ones were discovered, one called Eris which is bigger than Pluto (Pluto is actually smaller than the Earth's moon).
Scientists then defined the word 'planet' for the first time, and Pluto along with other small objects, were now called 'dwarf planet's.
This means there are only 8 planets in the Solar System, with Neptune being the furthest one away from the Sun.
Beryllium is obtained from two minerals called bertrandite and beryl with nearly all the world’s supply coming from a mine in Utah, USA.
Beryllium is very reactive towards oxygen and water, and so is not easy to obtain and purify. The current industrial method involves reaction of the ore with hydrogen fluoride to form beryllium fluoride which is then reduced using magnesium metal.
Beryllium is also found in aquamarine and emerald precious stones.
Berylllium is used in making alloys to make softer cheaper metals such as copper harder. Because beryllium is light and stable at very high temperatures it has been used in rocket nozzles and space telescopes. It is also fairly transparent to X-rays and other ionizing radiation so has been employed for windows for radiation and particle physics experiments. For example, it has been used to make components around detectors in the Large Hadron Collider.
Applications of beryllium metal are limited because beryllium-containing dusts are very toxic.
A vacuum cleaner has a fan inside, like an aeroplane’s propellers, that is powered by an electric motor. When the blades of the fan turn around, the air particles are forced away from the fan and the air pressure drops behind the fan.
Because this air pressure is less than the normal air pressure outside the vacuum cleaner, the fan sucks in air particles from outside and out through the back of the cleaner. Because of this difference in pressure, there is a space where there is less air particles than normal – this is called a vacuum and gives the cleaner its name.
The flowing air particles hit loose dust and dirt and the friction they make, carries the dust into the vacuum cleaner. Rolling brushes on the bottom of the cleaner help to knock the dust from the floor into the moving stream of air.
Inside, a filter bag, with holes big enough to let air particles through, but small enough to trap dust and dirt particles helps to keep all the dirt inside the cleaner.
Because it’s the movement of air that makes a vacuum cleaner work, it doesn’t have to be just oxygen; any gas would work. Because the air in our atmosphere is mostly nitrogen (78%) and oxygen (21%), then you could say that oxygen is used by vacuum cleaners, but it’s mostly nitrogen instead!
This is a good question as the Earth’s core is gradually solidifying as it loses heat and freezes. To read more about this, take a look at the answer to the question below: “How do we know the Earth's core is so hot?” Billions of years from now, the planet may have cooled so much (by losing heating to space) that the core will be entirely solid. This may have already happened to our neighbouring planet Mars which is around the same age as the Earth but which has cooled down much more because of its smaller size (about half the radius of Earth or one-seventh of its volume).
One of the most dramatic effects of the Earth’s core solidifying would be that the huge magnetic field that is generated there will die. This is because the magnetic field relies on the motion of the electrically-conducting iron liquid in the outer core (motion caused by its cooling by convection and by the rotation of the planet) to generate it. There is evidence that Mars had its own magnetic field but that it died around 4 billion years ago because the core became too cold to continue generating it. A planet’s magnetic field protects its surface and atmosphere from particles fired out by the sun (called the solar wind). Mars’s atmosphere is much thinner than the Earth’s in part because it does not have the protection of the magnetic field. So a short answer to your question is: if the core solidifies, the magnetic field will die and the atmosphere will be more prone to being blown away by the solar wind. However, by then this may be the least of our worries. The sun is expected to change from being a yellow dwarf star to being a red giant in the next few billions of years. When this happens, the entire planet will be gobbled up by it, magnetic field or not.
(Answered by Dr. Andy Biggin - Geophysicist at University of Liverpool)
Lava that is still inside a volcano is called magma. Lava can reach temperatures of 1200 degrees celsius, which is too hot for scientists to use a normal thermometer (the kind you use at home or in school). Instead, scientists use an instrument called a thermocouple.
This is made of two wires of different types of metal which are joined to an electrical source (usually a battery). When the electric current passes through point where the two wires are joined, the resistance of the current can be measured. This electrical resistance is very sensitive to the temperature, and so this can be measured using an ammeter and converted to a temperature reading.
The type of thermocouple used for measuring lava can work up to temperatures of 1600 degrees celsius, as the melting point of the two wires, and the ceramic insulation and stainless steel protecting the wires are all higher than the temperature of lava.
Another way of measuring the temperature is to do it from a short distance (remotely) using an instrument called an optical pyrometer. This is a bit like a telescope with filtered lenses. A scientist will point this at the lava and adjust an electrical filament (like in an old fashioned light bulb) until the two colours match. They can then work out how hot the lava is.
When you burn magnesium ribbon you get a very bright intense white flame and a trail of white smoke - you are left with a whitish ash/powder which is magnesium oxide.
The white smoke will also be magnesium oxide but in very fine particles which we can only see when they are gathered together as the smoke which will disperse in the air.
The chemical equation for this reaction is 2 Mg + O2 -> 2 MgO
This question can be answered in many ways, depending on what you mean by the most common country.
In terms of coal reserves (how much un-mined coal a country has), USA has the biggest coal reserves; 246,643 million tonnes, which is 27% of the world’s reserves.
This is followed by Russia and then China.
In terms of the largest coal producers, China is the biggest, producing 42.5% of the world’s coal (2782 million tonnes in 2008). This is followed by USA and then the European Union.
Australia is the largest exporter of coal, exporting 25.6% of the world’s coal in 2008 (252 million tonnes). Indonesia is the second largest coal exporter, and Russia is the third.
However, Japan is the largest coal importer, importing 19.4% of the world’s coal in 2008 (187 million tonnes). South Korea is the second largest coal importer, and India is the third.
When oxygen is cooled below -182.96 °C, it becomes a liquid of a pale blue colour.
Liquid oxygen is made by cooling and compressing air in an air separation plan. When the cooled air is warmed up, nitrogen will evaporate leaving the liquid oxygen.
Oxygen in its liquid state has many uses.
In the space industry, liquid oxygen is used in rocket fuel as a propellant, mixed with liquid hydrogen. This is because it is a powerful
oxidsing agent, that is, organic matter will buurn quickly in liquid oxygen. It has been used in the main engines of the Space Shuttle
In the aerospace industry, it can be used to provide breathing gas for military and commercial pilots.
In medicine, liquid oxygen can be used to improve the availablity of oxygen in conditions of, for example, surgical trauma, shock, carbon monoxide poisoning, or resuscitation of critically ill patients.
Average winter temperatures are around -34°C and average summer temperatures are around 0°C.
Compared with the South Pole, the North Pole is relatively warmer, because it is at sea level in the middle of an ocean, rather than high up in a land mass, as the South Pole is.
(Submitted by Azam & Adam)
When playing your xBox 360 or any other type of hand held gaming console controller, you are mostly using the muscles of your thumb and any one or more of your fingers.
The nine muscles of the thumb are split into two groups, extrinsic (those that start in your arm) and intrinsic (those that start in your hand).
If you use the controller too much, you may start to feel some discomfort in your thumb and finger muscles. This is a form of injury known as Repetitive Strain Injury (RSI) and can lead to stress of the tendons, nerves and ligaments in your hands.
In the gaming world, this type of injury is jokingly called ‘gamers’ grip’, Playstation Thumb or ‘Nintendonitis’(!), but it’s not just gaming consoles that are to blame. Repeated texting on your mobile can lead to the same type of problems.
The controller (or Wii-mote) is stuffed full of tiny motion sensors called accelerometers. These measure the acceleration (how much things speed up) of the controller in 3 directions (up / down, left / right and forwards / backwards). A microprocessor in the controller works out the movement of the player as well as the speed of the movement and then beams the signal across to the console using infra-red (a part of light that humans can’t see).
People are now using accelerometers to control loads of other things like vacuum cleaners, mobile phones and even to make 3D pictures on your computer screen!
Did you know?
Playing a Wii sports game where you move around burns 60 calories an hour more than when you play a game sitting on the sofa!
(Question submitted by Abby)
Lightning is thought to form from ice and water droplets colliding in a thundercloud. A large electrical spark forms from electrons moving from between the ice and water droplets. Electrons cannot be seen but when lightning flashes they are moving so fast that the air around them glows. The actual streak of lightning is the path the electrons follow when they move.
Thunder is formed by the heat from lightning compressing the air around in and forming a supersonic wave that decays into a sound wave that you hear as thunder. You always see the lightning first as light travels faster than sound does.
How to stay safe in a thunderstorm
If there's a thunderstorm, make sure you stay indoors and don't use any electrical equipment like the television, computer or telephone. If the lightning strikes the house, it will take the easiest route to earth, e.g. electrical cables or water pipes.
If you can't get indoors, avoid any high places, or tall isolated structures (towers, trees, etc.).
Did you know?
In June 2009, a teenage girl survived a direct hit by a lightning bolt thanks to wearing her iPod. The girl and her boyfriend were under a tree sheltering from the thunderstorm when the lightning struck.
The lightning passed through her headphones (not in her ears at the time!) and down into her mp3 player.
Experts think that lightning takes the easiest route to the ground and the metal contained in her mp3 player was the best conductor of electricity.
The mantle is a layer of the Earth which starts about 60 miles below the surface, and directly below the Earth's crust.
It is mainly made of a green coloured rock called peridotite. Because of the high temperatures and pressures at this depth, the mantle is plastic, which means that it flows very slowly.
This behaviour is the same as that of glass, which can also flow very slowy over time.
It is this plastic property of the mantle which helps the more rigid plates of the Earth's crust move about (called plate tectonics, or continental drift).
We think the Earth's heat comes from radioactive isoptopes in the mantle releasing energy that were present when the Earth was first formed.
Other heat is thought to be gravitational heat (from friction caused by heavier elements sinking down and lighter ones rising up).
Once the heat source ruins out, the core and the mantle of the earth will become solid and the Earth will be like the moon is now - a cold, dead planet.
(Question submitted by Andrew)
The temperature of lava as it erupts from a volcano can reach up to 1200 Celsius. The melting point of ceramics (pottery) is normally more than this (the exact temperature depends on what recipe has been used to make the ceramic) so no, lava won’t melt ceramic. Part of the process to make ceramics is baking in a kiln to very high temperatures.
Did you know?
In Mexico City ,lava flowed over ancient settlements and baked pieces of ceramic pottery that were there? We know that they were heated to over 600 Celsius as the magnetic information they contain was completely reset by the lava flow. It was not however hot enough to melt them.
(Answered by Dr. Mimi Hill - Geophysicist at University of Liverpool)
Scientists think that the temperature at the centre of the Earth isbetween 4000 and 7000 degrees Celsius. We can’t measure the temperature at the core directly, but because we think it is made mostly of iron, we can do experiments to compare how other materials behave at different temperatures and pressures, and guess at what temperatures iron melts at the same pressures as the core.
The temperature inside the Sun is though to be around 13.5 million degrees Celsius! This is the temperature at which nuclear fission can happen, hydrogen atoms fuse together to form Helium atoms. Huge amounts of energy are released by this reaction, and this energy travels out towards, cooling to around 6000 degrees Celsius at the surface of the Sun.
The huge amount of energy that is released by this fusion process is mainly due to the vast size of the Sun, rather than the production power (which is similar to the heat generated by a compost heap).
So, the centre of the Sun is much, much hotter than the centre of the Earth!
It is a very bad idea to taste beryllium as it is very toxic.
At some time someone must have tasted it because the early name was glucinum ( as in glucose) due to the sweet taste, but scientists have done things in the past that we would never do now!
So don’t try it!!
(Question submitted by Alex)
The geographic poles of the Earth are either end of the Earth's rotational axis (the line that the Earth's spins around). They are called the North and South pole. The magnetic poles are also at near to the geographic poles, but not quite. This is because, even though the spinning of the Earth helps to produce the magnetic field, through electrical conduction in the metal liquid outer core, the magnetic poles will 'wobble' a bit and can wander slowly around the geographic poles (this is called 'secular variation'). So, over thousands of years, the average position of the magnetic poles is similar to the geographic poles, but at any point in time, they are a bit off.
Did you know?
On some planets like Uranus, their magnetic poles are tilted far away from the geographic poles (by about 60 degrees!)
Aquamarine is the name given to the blue type of beryl, a crystalline mineral.
Beryl is often found with granitic pegamites, igneous rocks that have large interlocking crystals within them.
Pegmatites are formed in the Earth’s crust, either surrounding large magma chambers, (molten rock) or maybe by the squeezing of metamorphic rocks (rocks that have been changed from their original state) which releases hot fluids of the right temperature and chemistry to form pegmatites.
Did you know?
The largest known crystal of any mineral in the world was a beryl crystal from Madagascar. It was 18 metres long and 3.5 metres across!
(Question submitted by Rob)
The Earth is thought to be at 4.5 billion years old. The gases that made up the atmosphere at that time would have been very different from today’s atmosphere.
Scientists have been able to guess how much carbon dioxide was in the atmosphere around 1.2 billion years ago by using evidence from fossils.
By looking at fossils found in shale (a rock made from fine clay and mud laid down in quiet deep waters) from China, geologist have fired a tiny ion beam into the centre of these fossils, which destroys the organic carbon matter and measured the type of carbon ions that are given off.
Because carbon dioxide is more likely to form with carbon-13 ions, and the fact that the fossils lived near the surface of the sea, the atmospheric content of the atmosphere could be estimated.
Carbon dioxide values of about 10 times as high as present day levels were calculated.
How do scientists measure the temperature of the moon?
On board the Lunar Reconnaissance Orbiter (LRO), there is an instrument called Diviner which measures the amount of infrared radiation coming from the Moon. The more infrared radiation that is emitted, the hotter the surface of the Moon is.
During the day, in areas of direct sunlight, the temperature can reach up to 107 degrees centigrade, hot enough to boil water.
During the night, the temperature can fall to -180 degrees centigrade!
And because the Moon takes 27 days to rotate, days and nights are 13 Earth days long!
That’s why lunar astronauts needed special suits to keep them cool in the day and warm at night.
Humus is the word used to describe stable organic matter found in soil. Humus is formed from the decomposition of organic matter (plant remains, and will not break down any further.
Humus is an important part of soil as it helps the soil keep its moisture and stores nutrients, vital to the plants and animals living within and on the soil.
(Question submitted by Anna)
The boiling point of NaCl (sodium chloride or common salt) is 1413 degrees celsius. When NaCl is dissolved in water to the point of saturation, the boiling point of saturated salt solution near to 108.7 degrees celsius.
The difference in boiling points is because when dissolved in water, the framework of sodium chloride is broken, and the Na+ and Cl- ions are surrounded by water molecules.
The heat from lava (normally between 700 and 1200 degrees celsius), will be transferred to the tree by conduction (direct contact between the tree and the hot liquid) and convection (heat transferred by motion of air around the lava).
Copper does not burn in a flame but just turns black - this blackening is the copper oxide - a result of the following chemical reaction.
2 Cu + O2 -> 2 CuO or Copper + Oxygen -> Copper Oxide
When sodium is added to water, the reaction produces heat (this is called an exothermic reaction) and melts the sodium.
The reaction can be written as:
2 Na + 2 H2O ----> 2 NaOH + H2
Sodium hydroxide and hydrogen gas is produced. The heat ignites the hydrogen which then burns with a bright flame.
The see reaction take place at: http://www2.uni-siegen.de/~pci/versuche/english/v44-1-1.html