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Question
The atomic number and the mass number of an element is 26 and 56 respectively. Calculate the number of electrons, protons and neutrons in its atom. Draw the structure.
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Solution
Given:
Atomic number A = 26
Mass number A = 56
No. of Protons P = ?
No. of Electrons = ?
No. of Neutrons N = ?
Name of the element is Iron (Fe)
No. of proton (P) = 26
Mass number A = n+p
56 = n = 26
n = 56-26
∴ No. of neutrons n = 30
In an element No. of protons and No. of electrons is equal.
∴No of electrons = no. of protons
= 26
Structure of Iron:
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