Answer:
0.429 M
Explanation:
To find the molarity, you need to (1) convert grams to moles (using the molar mass), then (2) convert mL to L, and then (3) calculate the molarity (using the molarity ratio).
(Step 1)
Molar Mass (NaCl): 22.990 g/mol + 35.453 g/mol
Molar Mass (NaCl): 58.443 g/mol
18.8 grams NaCl 1 mole
-------------------------- x ------------------------ = 0.322 moles NaCl
58.443 grams
(Step 2)
1,000 mL = L
750.0 mL 1 L
------------------ x ----------------- = 0.7500 L
1,000 mL
(Step 3)
Molarity (M) = moles / volume (L)
Molarity = 0.332 moles / 0.7500 L
Molarity = 0.429 M
