A student is making a solution of sodium carbonate (Na2CO3) they mix 0.79 grams of sodium carbonate into 50.0 mL of water. What is the molarity of the sodium carbonate solution? A 0.15 M Na2CO3
B 1.5 x 10^-4 M Na2CO3
C 6.7 M Na2CO3
D 15.8 M NaCO3

[Na₂CO₃] = 0.15 M

Explanation:

Molarity is a type of concentration.

It is useful for solutions, to say how many moles of solute are contained in 1L of solution.

We can also say, that molarity are the mmoles of solute in 1 mL of solution.

In this case, our solute is the Na₂CO₃.

We convert mass to moles: 0.79 g . 1 mol / 106g = 7.45×10⁻³ moles

We convert moles to mmoles:  7.45×10⁻³ mol . 1000 mmol / 1mol = 7.45 mmol

M = mmol / mL

M = 7.45 mmol / 50 mL = 0.15 M

Option A is the right answer.

right

explanation: