Chapter P2, Problem 1MCPE

To determine

The element after removing two protons and two neutrons from the nucleus of neon-20.

Answer to Problem 1MCPE

Solution:

Oxygen-16 is the element which we will get after removing two protons and two neutrons from the nucleus of neon-20.So, option(d) is correct.

Explanation of Solution

Given

Two protons and two neutrons are removed from the nucleus of neon-20.

Formula used:

$A=Z+N$ Where $A$ is mass no. of element
$Z$ is Atomic no. of element.
$N$ is no. of neutrons.
Calculation

Since,atomic no.( $Z$ ) of neon is 10 and mass no.(A) is 20. No. of neutrons will be 10 from:
$N=20-10=10$

And, we know that no. of protons is the atomic number.
Therefore, when we remove two protons and two neutrons, then $Z$ become 8 and no. of neutrons also become 8. So, $A=8+8$$=16$.
$Z$ is no. of protons which is 8.
So, the element is oxygen-16 whose atomic number is 8 and mass number is 16.

Conclusion:

Using $A=Z+N$, we found that oxygen-16 is the element which we got after removing two protons and two neutrons from the nucleus of neon-20.