A soft silvery metal has two naturally occurring isotopes: mass 84.9118, accounting for 72.15% and mass 86.9092, accounting for 27.85%. The atomic weight of this metal would be:

The atomic weight of the metal would be 85.47.

Explanation:

Mass of isotope 1 of metal = 84.9118

% abundance of isotope 1 of metal = 72.15% =

Mass of isotope 2 of metal= 86.9092

% abundance of isotope 2 of metal = 27.85% =

Formula used for average atomic mass of an element :

Therefore, the atomic weight of the metal would be 85.47.

particle   p is an electron and particle q is a neutron

the answer is c. nacl