Question

What is the molar mass of a compound if 25.0 g of the compound dissolved in 750. Ml gives a molarity of 0.290 m?

Answer 1

Answer:

115g/mol

Explanation:

To get the molar mass, we know that the it is equal to the mass divided by the number of moles. We have the mass but we do not have the number of moles.

We get this by working through the solution information. Firstly, we need to know the number of moles in 750ml for a molarity of 0.29m

Now, since 0.29 moles is present in 1000ml, x moles will be present in 750ml

The value of x is obtained as follows:

x = (750 * 0.29)/1000 = 0.2175 moles

Now since we have the number of moles, we can then obtain the molar mass.

Molar mass = mass/number of moles = 25.0g/0.2175 = 114.94 approximately 105g/mol