Tag Archives: science

Radioactive Decay

Radioactive isotopes of elements have unstable arrangement of neutrons and protons in their nuclei. To become more stable, they emit alpha or beta particles. But this changes the number of protons and neutrons in the nucleus resulting in the formation … Continue reading

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Nuclear Radiation

Discovery: Henry Becquerel discovered radioactivity accidentally in 1896.   Nuclear radiation: Some elements contain atoms with unstable nuclei. With time, the unstable nucleus disintegrates. While doing so, it shoots out a tiny particle and sometimes wave energy as well. Since … Continue reading

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m’s notes on nutrition

         

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Burning

1. Is burning a chemical reaction? 2. What happens when substances burn? 3. What are oxidation reactions? 4. Is rusting an oxidation reaction? Why? 5. Rusting is a very slow type of burning reaction. True or false. 6. What are … Continue reading

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Fast and slow reactions

  1.  Define the rate of a reaction. 2.  _________ are chemical reactions that take place very quickly and release a lot of heat, light and noise. 3.  _________ and _________ are examples of slow chemical reactions. 4.  What are … Continue reading

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