Question

Calculate the number of moles of KOH in 6.70 mL of a 0.480 M KOH solution. (Enter your answer in scientific notation.)

Answer 1

Answer:

3.2×10^-3 mol

Explanation:

The equation for molarity is M= n/L. Where "M" is Molarity, "n" is the number of moles of solute, and "L" is the total liters in solution.

The question gives you the volume in mL, so to convert "mL" to "L" you need to divide by 1000. (6.70mL/ 1000L)= 0.0067L.

Now you can plug the numbers into the equation. 0.480M= n/ 0.0067L), multiply (0.480M×0.0067L)= 0.003216 mol. The scientific notation is 3.2×10^-3, 10^-3 because you move the decimal back three times and 3.2 because there are 2 sig figs.