Question

What is the molarity of a solution that contains 17g of NH₃ in 0.50L of solution?

Answer 1

Molar mass of Ammonia:-

$\\ \sf\longmapsto NH_3$

$\\ \sf\longmapsto 14u+3(1u)$

$\\ \sf\longmapsto 14u+3u$

$\\ \sf\longmapsto 17u$

$\\ \sf\longmapsto 17g/mol$

Moles of Ammonia:-

$\boxed{\sf No\:of\:moles =\dfrac{Given\:mass}{Molar\:mass}}$

$\\ \sf\longmapsto No\:of\:moles=\dfrac{17}{17}$

$\\ \sf\longmapsto No\;of\:moles=1mol$

• Volume of solution=0.50L

We know

$\boxed{\sf Molarity=\dfrac{Moles\:of\:solute}{Volume\:of\: Solution\:in\:L}}$

$\\ \sf\longmapsto Molarity=\dfrac{1}{0.50}$

$\\ \sf\longmapsto Molarity=2M$

Answer 2

Explanation:

Because molarity is mol/L, we'll have to convert 17g to mol.

After obtaining the mol, we'll divide that by the volume to obtain Molarity.