Atomic number refers to the number of protons within the nuclei of an element's atoms (and therefore the number of electrons) while mass number refers to the number of protons and neutrons within the nucleus.
Answer:
J.J.Thomson discovered negatively charged particles by cathode ray tube experiment in the year 1897. The particles were name electrons.
A solid, a liquid or a gas.
The formula for water is H2O so there would have to be two Hyrdogens and one oxygen. Therefore it would be 4g of Hydrogen and 16g of Oxygen leaving you with 20g.
The answer is D.
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