Question

What is the mass of $6.023 \times {10^{23}}$molecules of $N{H_3}$?
A.$45.06g$
B.$19.06g$
C.$17.04g$
D.$31.02g$

Answer 1

We must need to know that the proportionality factor that relates the number of constituent particles in a sample to the amount of material in that sample is the Avogadro constant. The reciprocal mole is its SI unit.
The value of the constant of Avogadro was chosen in such a way that the mass of one mole of a chemical compound, in grams, is numerically equal (for all practical purposes) to the mass of one molecule of the compound, in Daltons (universal atomic mass units); 1 Dalton is one by twelve.
The mass of one atom of carbon-12, which is roughly the mass of one nucleon (proton or neutron). A mole of carbon atoms comprises twelve grams of carbon.

Complete step by step answer:
As we know that in chemistry, the molar mass of a chemical compound is defined as the mass of that compound's sample, divided by the amount of substance measured in moles in that sample. A bulk, not molecular, the property of a substance is the molar mass.
The mass of $6.023 \times {10^{23}}$ molecules of $N{H_3}$​ is the mass of one mole of $N{H_3}$​ i.e. the molar mass of $N{H_3}$
One mole of $N{H_3}$​ has $6.023 \times {10^{23}}$ molecules of $N{H_3}$
Molar mass is $= 14.01 + 3(1.01) = 17.04g$
Option C is correct option as molar mass is $17.04g$

Note:
We must have to remember that the ammonia, consisting of one atom of nitrogen and three atoms of hydrogen, is a chemical compound. Ammonia is a colourless gas that can be readily liquefied and is lighter than air. Ammonia is made up of one chemical compound. An atom of nitrogen and three atoms of hydrogen, and comes in a trigonal pyramid shape.
Ammonia is a nitrogen and hydrogen alloy with a formula. Ammonia, a stable binary hydride, and the simplest pnictogen hydride, is a colourless gas with a pungent smell that is distinctive.