Question

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

Answer 1

Answer:

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

Answer 2

Answer:

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)