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anyanavicka [17]
2 years ago
14

In the symbol 42He, the subscript 2 is the _____ for helium and the superscript 4 is the _____ for helium. atomic mass; atomic n

umber atomic number; atomic mass mass number; atomic number atomic number; mass number
Physics
2 answers:
aleksklad [387]2 years ago
6 0
Mass number ; atomic number
Scrat [10]2 years ago
3 0

Answer:

2 is the atomic number while 4 is the mass number.

Explanation:

The symbol of an element is Z X A. Where Z is the number of protons or called atomic number of the element and A be the sum of number of protons and neutrons or called mass number of that element,

Here 42He,

Z = 2, it means atomic number is 2, which shows that number of proton are 2.

A = 4, it means mass number, which shows that the sum of number of neutrons and protons are 4.

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