How did we discover DNA? DNA was first discovered in 1869, but it wasn’t identified as the substance carrying hereditary information until 1944, and its structure wasn’t discovered until 1953. DNA stands for deoxyribonucleic acid. Broken down, “deoxyribo” refers to the sugar part of the DNA, “nucleic” means it is found within the nucleus of […]
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Who came up with the idea for the periodic table? The periodic table was first made by a Russian chemist called Dmitri Mendeleev in 1869. You have definitely seen the periodic table of elements. Currently, it has 118 elements on it. The first 94 of those are naturally occurring elements and the other 24 have
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Why is fire hot? Fire is hot because thermal energy is released from the materials when chemical bonds are rearranged during a combustion reaction. New, stronger bonds form and the energy difference comes out as heat and light When you burn most fuels, you are releasing the chemical potential energy that they have stored inside
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What is highly enriched uranium? It is uranium that contains 20% or more uranium-235, which is the type of uranium most useful for a sustained nuclear chain reaction. Uranium is a fairly common element that can be found in rocks, soil, and water. It is not as rare as many people probably imagine. There is
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Why does friction produce heat? Friction produces heat because mechanical energy has to go somewhere, and some of it is converted into the random movement of atoms and molecules, which is heat. Sometimes we need friction to produce heat and sometimes we don’t want it to. If you have ever been out in the cold
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What is tuberculosis? Tuberculosis (TB) is a contagious, airborne bacterial infection caused by Mycobacterium tuberculosis. If you have read any books set in Victorian London, you will have seen character after character die of “consumption.” It killed two of the famous Bronte sisters, as well as two of their other sisters and their brother. In
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What does E = mc² mean? E = mc² means that mass and energy are two ways of describing the same physical thing. In everyday life, mass feels like “stuff” and energy feels like “activity,” but Einstein showed that they are connected. If a system loses energy, it also loses mass. If it gains energy,
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What did Marie Curie win two Nobel Prizes for? She won the Nobel Prize in Physics in 1903 for her research in radiation (shared with her husband), and she won the Nobel Prize in Chemistry in 1911 for discovering radium, polonium, and isolating radium. Marie Curie is not the only person to have won two
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Are all snowflakes really different? Theoretically, yes, all snowflakes are different, but it is an issue of probability, and there is obviously no way to know for sure. Snowflakes form when the air is cold enough for water droplets to freeze. It is very difficult for them to freeze on their own; it is much
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What is a geothermal heat pump? A geothermal heat pump is a way of heating and cooling buildings by exchanging their heat with the ground. Natural objects obviously gain and lose heat depending on the amount of sunlight, what they are made of, the weather, where they are, and a whole host of other conditions.
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