Question

If an atom has 15 protons, 12 neutrons, and 17 electrons, what is the atom's electrical charge? A. -5 B. -2 C. +3 D. +5

Answer 1

Answer:

B. -2

Explanation:

The total charge on an atom is the sum of all individual charges present in it. Therefore, the total charge on this atom is given by the following formula:

$q = (n_p)(q_p)+(n_e)(q_e)+(n_n)(q_n)$

where,

q = total charge on atom = ?

$n_p$ = no. of protons in the atom = 15

$n_e$ = no. of electrons in the atom = 17

$n_n$ = no. of neutrons in the atom = 12

$q_p$ = charge on proton = +1

$q_e$ = charge on electron = -1

$q_n$ = charge on neutron = 0

Therefore,

$q = (15)(1)+(17)(-1)+(12)(0)\\q=-2$

Hence the correct option is:

B. -2