2.50 G Cucl2 Equals Moles

Question: A sample of carbon-12 has a mass of 6.00 g. How many atoms of carbon-12 are in the sample?

3.01 × 1023

6.02 × 1023

1.20 × 1024

3.60 × 1024

How many moles of carbon are in the sample?

0.500

1.00

6.00

12.0

Answer: 3.01 x 10^23

.500

Question: The molar mass of copper(II) chloride (CuCl2) is 134.45 g/mol. How many formula units of CuCl2 are present in 17.6 g of CuCl2?

7.88 × 1022 formula units

1.84 × 1023 formula units

1.91 × 1023 formula units

1.42 × 1024 formula units

Answer: 7.88 x 10^22 formula units

Question: To calculate molar mass

Answer: find the number of grams in each elements, find the number of grams of each element in one mole, and add together

Question: The molar mass of barium nitrate (Ba(NO3)2) is 261.35 g/mol. What is the mass of 5.30 × 1022 formula units of Ba(NO3)2?

0.0900 g

12.0 g

23.0 g

3,130 g

Answer: 23.0g

Question: A gas cylinder contains exactly 15 moles of oxygen gas (O2). How many molecules of oxygen are in the cylinder?

4.01 × 1022 molecules

6.02 × 1023 molecules

9.03 × 1024 molecules

2.89 × 1026 molecules

Answer: 9.03 x 10^24