A solution is made by dissolving 5.84 grams of NaCl in enough distilled water to give a final volume of 1.00 L. What is the molarity of the solution Group of answer choices

0.0250 M

0.400 M

0.100 M

1.00 M

Explanation:

Molarity is a measure of concentration in moles per liter.

The solution has 5.84 grams of sodium chloride or NaCl and a volume of 1.00 liters.

We are given the mass of solute in grams, so we must convert to moles. This requires the molar mass, or the mass of 1 mole of a substance. These values are found on the Periodic Table as the atomic masses, but the units are grams per mole, not atomic mass units.

We have the compound sodium chloride, so look up the molar masses of the individual elements: sodium and chlorine.

The chemical formula (NaCl) contains no subscripts, so there is 1 mole of each element in 1 mole of the compound. Add the 2 molar masses to find the compound's molar mass.

There are 58.4397693 grams of sodium chloride in 1 mole. We will use dimensional analysis and create a ratio using this information.

We are converting 5.84 grams to moles, so we multiply by that value.

Flip the ratio. It remains equivalent and the units of grams of sodium chloride cancel.

We can use the number of moles we just calculated to find the molarity. Remember there is 1 liter of solution.

The original measurements of mass and volume have 3 significant figures, so our answer must have the same. For the number we calculated, that is the thousandths place. The 9 in the ten-thousandths place tells us to round the 9 to a 0, but then we must also the next 9 to a 0, and the 0 to a 1.

1 mole per liter is 1 molar or M. We can convert the units.

The molarity of the solution is 0.100 M.