Sa solution is made by dissolving 26.42 g of (NH4) 2SO4 in enough H2O to make 50.00 mL of solution. what is the molarity of the solution

The answer is 0.2 M.

Molarity is a measure of the concentration of solute in a solution

c = n : V

c - concentration of solute,

n - number of moles of solute

V - volume of solution

We know:

V = 50.00 mL = 0.05 L

c = ?

n = ?

Let's calculate concentration:

c = m / (V * Mr)

The molar mass of (NH4) 2SO4 is the sum of atomic masses (Ar) of its elements):

Mr ((NH4) 2SO4) = 2Ar (N) + 8 Ar (H) + Ar (S) + 4Ar (O)

= 2 * 14 + 8 * 1 + 32 + 4 * 16 =

= 28 + 8 + 32 + 64 =

= 132 g/mol

c = 26.42 g / (0.05 L * 132g / mol) = 26.42 g / 6.6 L*g/mol = 4 mol/L = 4 M

Now, calculate molarity:

c = n : V

n = c * V

n = 4 mol/L * 0.05 L

n = 0.2 mol