Question

Q. 3. The atomic number of the element Be is 4, its mass number is​

Answer 1

Answer:

Its atomic number is 2, so it has two protons in its nucleus. Its nucleus also contains two neutrons. Since 2+2=4, we know that the mass number of the helium atom is 4.

Explanation:

PLS MARK AS BRANLIEST

Answer 2

mass is 8amu

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