Question

What is the total number of molecules in 34 grams of NH3?

Answer 1

34g(NH3) is 2 moles (NH3)  

In one mole there are 6.022 x 10^23 molecules (Avogadro Numbet).  

In two moles there are 2 x 6.022 x 10^23 moles = 1.2044 x 10^24 molecules.

A.D

Answer 2

Given - Mass of ammonia 34 gram

Find - Total number of molecules

Solution - The molar mass of ammonia is 17 grams/mole.

So, as per the above information, 1 mole of ammonia weighs 17 gram

Hence, 34-gram ammonia will have number of moles = 34/17

Number of moles = 2

Now, we know 1 mole of any molecule contains number of molecules equivalent to Avogadro's number which is 6.022*10²³.

So, 2 moles will have molecules = 2*6.022*10²³

Number of molecules = 1.2*10²⁴

Thus, the total number of molecules in 34 grams of ammonia is 1.2*10²⁴