Elements

• All the atoms that make up a single element have the same number of protons.
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• All atoms except those of the simplest form of hydrogen also contain neutrons.
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• Electrons circle the nucleus at different distances depending on how much energy they have.

BSL Version

(Revision: See Atomic structure)

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What is Building Elements?
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• The basic chemicals of the Universe are elements – material produced by or used in a reaction involving changes in atoms, and they cannot be broken down into other substances – solid mass.
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• elements are formed entirely of atoms that contain the same number of protons in their nucleus for example;
  – for example:
  ………– all hydrogen atoms have one proton.
  ………– all helium atoms have two proton.
  ………– all lithium atoms have three proton.
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• more than 100 elements are known.
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• simplest and lightest elements;
  – hydrogen and helium
  – formed nearly 14 billion years ago in the history of the Universe. (See Big Bang)
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What is other Elements?
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• other elements formed;
  – nucleus of the atoms of the light elements joined by nuclear fusion.
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• nuclear fusion of element atoms;
  – happens deep inside the stars at the end of their lives.
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• lighter elements;
  – such as oxygen and carbon ~ the first to form.
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• helium nuclei fuse;
  – with oxygen and neon atoms to form atoms, such as silicon, magnesium and calcium.
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• heavy atoms form;
  – when supergiant stars reach the end of their life and collapse ~ boosting the pressure of the gravity in their core. (see below)

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BSL Version