If a sample of KF has a mass of 100.0 grams, how many moles of KF are present in the sample?

a. 1.000 mol
b. 1.721 mol
c. 0.5810 mol
d. 58.10 mol
e. 10.00 mol

The answer to your question is the letter b. 1.721 moles

Explanation:

Data

mass of KF = 100 g

The Number of moles = ?

Process

1.- Calculate the Molar mass of KF using the periodic table

K = 39.1

F = 19

Molar mass = 39.1 + 19

                   = 58.1 g

2.- Calculate the number of moles of KF

                      58.1 g of KF 1 mol

                      100 g  of KF  x

                      x = (100 x 1) / 58.1

                      x = 100 / 58.1

                     x = 1.721 moles

In a sample of 100.0 grams KF we have 1.721 moles of KF present (option B is correct)

Explanation:

Step 1: Data given

Mass of KF = 100.0 grams

Atomic mass of K= 39.10 g/mol

Atomic mass of F = 19.00 g/mol

Step 2: Calculate molar mass of KF

Molar mass KF = 39.10 + 19.00 = 58.10 g/mol

Step 3: Calculate moles of KF in the sample

Moles = mass / molar mass

Moles KF = 100.0 grams / 58.10 g/mol

Moles KF = 1.721 moles

In a sample of 100.0 grams KF we have 1.721 moles of KF present (option B is correct)

the volume increases