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Question
Define – Atom.
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Solution
An atom is the smallest particle of a chemical element that retains its chemical properties.
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Is it possible to see atoms these days ? Explain your answer.
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Project.
To have an idea of what atoms are, students can be asked to construct atoms using pipe cleaners (thin metal wires-electron shells), pompoms (balls-different colours for protons and neutrons) and beads (electrons). Students will love and enjoy putting them together and they look great hanging from the ceiling in the classroom.
Which of the following statements made by Dalton has not undergone any change?
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Atoms of different elements having ______ mass numbers, but ______ atomic numbers are called isobars.
