An element of atomic weight 40 has $2,8,8,2$ as the electronic configuration. Which one of the following…

An element of atomic weight 40 has $2,8,8,2$ as the electronic configuration. Which one of the following statements regarding this element is not correct?
  1. it belongs to II group of the periodic table
  2. it has 20 neutrons
  3. the formula of its oxide is $\mathrm{MO}_{2}$
  4. it belongs to 4 th period of the periodic table

Solution

It's valency is 2. So, it will form MO type compound. Hence, (3) is incorrect.

Asked in: JEE-TOPICTESTS-CHEMISTRY

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