Calculate the masses of
(i) `2.00` gram atoms of chlorine
(ii) `2.00` gram molecules of chlorine
(iii) `10.50` gram molecules of ammonia.

Explanation

(i) The atomic mass of chlorine `(Cl) = 35.45` amu
`therefore` The gram atomic mass of chlorine `= 35.45` g
Since, mass in grams `=` Number of gram atoms `xx` gram atomic mass
We have, mass of chlorine `= 2.00 xx 35.45 = 70.9` g
(ii) The molecular mass of chlorine `(Cl_(2))= 70.9 g`
`therefore` The gram molecular mass of `Cl_(2) = 70.9 g`
Since, mass in grams `=` Number of gram molecules `xx` gram molecular mass
We have, mass of chlorine `= 2.00 xx 70.9 = 1.42 xx 10^(2)`g
(iii) The molecular mass of ammonia `(NH_(3)) = 14.01 + (3 xx 1.008) = 17.034` amu
The gram molecular mass of `NH_3= 17.034` g
Hence, we have mass of `NH_(3) = 10.50 xx 17.034 = 178.8` g