Can I please get the answer to this question???

Question

How many moles of NaOH are present in 32.0 mL of 0.220 M NaOH?

moles__________

Answer 1

Hello, Janet,

Molar, M, is defined as "moles/liter." A 1 M solution of NaOH has 1 mole of NaOH per every 1 liter (1,000 ml) of solvent, water. To answer this question, rely on the units to guide your calculation. 0.220M NaOH can be rewritten as 0.220moles NaOH/1,000 ml soultion. 32.0 ml would therefore contain:

(32.0 ml)*(0.220moles NaOH/1,000 ml) = 0.00704 moles of NaOH, to 3 sig figs.

Bob

Answer 2

Molarity measures the concentration of a solution measured by the following equation:

M = mol of solute / liters of solution

Substitute the given information into the formula and solve for the unknown mols, x. Also keep in mind that 32mL = 0.032L since 1000mL = 1L

0.220M = x / 0.032L .....multiply both sides by the denominator liters to isolate x

x = 0.00704 mol

Conversions/Dimensional-Analysis Method:

Molarity is the ratio of mol/L as stated in the formula above. So 0.220M will be utilized as a conversion factor 0.220mol/L. So, the conversion will start with the given volume. Ratios are setup and multiplied to cancel units are yield the desired final unit.

32.0 mL x (1L / 1000mL) x (0.220mol / 1L) = 0.00704 mol