If the concentration of sodium carbonate in water is 12.8 ppm,what is the molarity of Na₂CO₃(aq)? The molar mass of Na₂CO₃ is 106.0 g/mol.Assume the density of the solution is 1.00 g/mL. A) 8.28 $\times$ 10^-6 M B) 1.21 $\times$ 10^-4 M C) 1.36 $\times$ 10^-3 M D) 0.136 M E) 0.121 M

Question

Quizplus · Accepted Answer

Step 1: Convert ppm to g/L
12.8 ppm = 12.8 mg/L = 0.0128 g/L

Step 2: Calculate the number of moles of Na2CO3
mol Na2CO3 = (0.0128 g/L)/(106.0 g/mol) = 1.21 × 10^-4 mol/L

Step 3: Convert mol/L to M (mol/L)
M = (1.21 × 10^-4 mol/L)/(1 L/1000 mL) = 1.21 × 10^-4 × 1000 M = 1.21 × 10^-4 M
= 1.21 × 10^-4 M ≈ 1.21 × 10^-4 M

Note: The density of the solution was not used in this calculation.

If the Concentration of Sodium Carbonate in Water Is 12 ×\times×

If the Concentration of Sodium Carbonate in Water Is 12 $\times$