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प्रश्न
Define: Mass number
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उत्तर
Mass number— Mass number is the sum of the number of protons and neutrons present in the nucleus of an atom. It is denoted by A.
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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.
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