Ask the expert
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!
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.
(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!
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.
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.
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.
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!
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!
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!
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.
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 laid down from the sea millions of 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 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)
Even though we say the Earth’s magnetic field is similar to the effect of a giant bar magnet in the centre, it’s unlikely that the bar magnet is real. We know this because scientists can use earthquakes to discover what’s inside the Earth.
When an earthquake happens, shock waves ripple out from its source all the way through the centre of the Earth and are reflected back to the surface.
Some shock waves can pass through both solids and liquids, but some can only go through solids. By measuring the time that these different waves reach the surface after the earthquake, scientists can work out that the Earth is made of different layers, some solid and some liquid.
It is the liquid layer (probably made of hot liquid iron) that makes up the outer core of the earth and is probably the source of the Earth’s magnetic field. The liquid rotates around as the Earth spins and generates electricity and the magnetic field, like a giant generator.
This magnetic field won’t last forever, as the Earth is gradually cooling down, and the liquid iron outer core will eventually freeze up. Then there will only be a very weak magnetic field from the iron-rich rocks at the surface of the Earth. This will be like what the planet Mars is like today.