Moles Conversion Practice

Multiple Choice

Which of the following dimensional analysis setups will correctly convert 27.76g of Li to atoms of Li?

• A

• B

• C

• D

Multiple Choice

Which conversion factor should be used to solve the following, "How many moles are in 28 grams of CO₂?"

• 1 mol = 22.4 L 

• 1 mol = 44.01 g

• 1 mol = 6.02x10²³ atoms

• more than one

Multiple Choice

Which conversion factor should be used to solve the following, "Find the mass in grams of 2.00 x 10²³ molecules of F₂."

• 1 mol = 22.4 L 

• 1 mol = 38.00 g

• 1 mol = 6.02x10²³ atoms

• more than one

Multiple Choice

What are the units for molar mass?

• grams

• amu

• grams per mole

• liters

Multiple Choice

Which of the following would have the highest number of moles?

• 4 g CO₂

• 15 g H₂O

• 22 g NaCl

• 100 g AgCl

Multiple Choice

How many molecules are in 25 mole of NaCl?

• 1.51x10²³

• 146

• 4.15

• 1.51x10²⁵

Multiple Choice

How many molecules are in 3.6 grams of NaCl?

• 0.06

• 1.0x10²¹

• 1.3x10²⁶

• 3.7x10²²

Multiple Choice

What should go in the question mark spot?

$$57.2\ grams\ NiS\ \times\ \frac{1\ mol}{?}=0.63\ mol$$  

• $$6.02x10^{23}\ mc$$  

• 1 mole

• 90.75 grams

• 57.2 grams

Multiple Choice

If you start with $$8.47x10^{24}\ molecules$$   , how many conversion fractions does it take to convert to grams?

• 1

• 2

Multiple Choice

How many moles are in $$3.92x10^{23}$$  molecules of $$CaF_2$$  ?

Which part of the setup is incorrect?

$$3.92x10^{23}\ molecules\ \times\ \frac{1\ mole}{78.08\ g}$$  

• $$3.92x10^{23}\ molecules$$  

• 1 mole

• 78.08 g

Multiple Choice

How many grams are in $$9.28x10^{23}\ molecules$$  of NaCl?

Choose the correct setup.

• $$9.28x10^{23}\ molecules\ \times\frac{6.02x10^{23}\ grams}{1\ mole}$$  

• $$9.28x10^{23}\ molecules\ \times\frac{6.02x10^{23}\ mc}{1\ mole}\times\frac{58.44\ g}{1\ mole}$$  

• $$9.28x10^{23}\ molecules\ \times\frac{1\ mole}{6.02x10^{23}\ mc}\times\frac{58.44\ g}{1\ mole}$$  

• $$9.28x10^{23}\ molecules\ \times\frac{58.44\ g}{1\ mole}$$  

Fill in the Blank

How many grams are in 2.9 moles of $$SiCl_4$$  ? Fill in the missing information.

$$2.9\ mol\ \times\ \frac{?\ grams}{1\ mole}=492.68\ g\ SiCl_4$$  

Fill in the Blank

How many molecules are in 4.93 moles of $$Ga_2S_3$$  ? Fill in the missing information.

$$4.93\ mol\ \times\ \frac{?\ molecules}{1\ mole}$$  

Multiple Choice

If you're starting with $$7.31x10^{24}\ molecules$$  of SrS and you want to convert to moles, what would go on the bottom of the conversion fraction?

$$7.31x10^{24}\ molecules\ \times\frac{ }{??????????????}$$  

• $$6.02x10^{23}\ molecules$$  

• 1 mole

• 119.68 g

Multiple Choice

What is the molar mass of Al₂(CO₃)₃?

• 113.97 g/mol

• 137.99 g/mol

• 233.99 g/mol

• 185.99 g/mol

Multiple Choice

If you have 82.21 grams of NO₂, how many molecules do you have?

Pick the correct setup.

• $$82.21\ g\ \times\frac{1\ mol}{46.01\ g}\times\frac{1\ mol}{6.02x10^{23}\ molecules}$$  

• $$82.21\ g\ \times\frac{1\ mol}{46.01\ g}\times\frac{6.02x10^{23}\ molecules}{1\ mol}$$  

• $$82.21\ g\ \times\frac{6.02x10^{23}\ molecules}{1\ mol}$$  

• $$82.21\ g\ \times\frac{1\ mol}{46.01\ g}$$  

Multiple Choice

How many moles are in 2.67x10²⁴ molecules of H₂O?

What is the missing piece?

$$2.67x10^{24}\ molecules\times\frac{???????????}{6.02x10^{23}\ mc}$$  

• 6.02x10²³ mc

• 1 mole

• 18.016 grams

• 2.67x10²⁴ mc

Multiple Choice

If you're starting with 82.21 grams of PH₃ and you want to convert to moles, what would go on the bottom of the conversion fraction?

$$82.21\ grams\ \times\frac{ }{??????????????????}$$   

• 1 mol

• 33.994 grams

• 6.02x10²³ mc

• 82.21 grams

Multiple Choice

How many molecules are in 2.50 mol of NaCl?

• 1.51x10²³

• 146

• 4.15

• 1.51x10²⁴

Multiple Choice

How many atoms of carbon are in 6.00g of carbon?

• 1.20x10²⁴atoms C
• 6.02x10²³atoms C
• 3.01x10²³atoms C
• 1.50x10²³atoms C

Multiple Choice

How many steps are in a gram to mole conversion?

• 1
• 2
• 3
• 4

Multiple Choice

What is the mass of one mole of silver?

• 32.06 g

• 107.87 g

• 14.01 g

• 22.99 g

THE MOLE

• A unit of Measure

• Easier then measuring each individual particle

• Equal to the Molar Mass of each element or compound

• Ex: 12.011grams Carbon = 1 Mole

Multiple Choice

What is the molar mass of Oxygen?

• 8 grams

• 8 moles

• 15.999 grams

• 15.999 moles

Multiple Choice

What is the molar mass of Hydrogen?

• 2 moles

• 2 grams

• 1.008 moles

• 1.008 grams

Gram To Mole Conversion

• Always starting with the amount of grams given in the problem.

• Use the conversion factor 1 mole over the Atomic mass (molar mass) of the element or compound.

Multiple Choice

How many moles is 4 grams of silicon?

• 4 moles

• 0.14 moles

• 28.085 moles

• 1.4 moles

Multiple Choice

How many moles is 19.5 grams of Sodium?

• 19.5 moles

• 0.85 moles

• 22.99 moles

• 8.5 moles

Calculating Molar Mass of a Compound

• Determine the number of atoms of each element

• Multiply the number of atoms by the atomic mass of each element

• Add the molar masses of each element together for the molar mass of the compound

Multiple Choice

Which of the following dimensional analysis setups will correctly convert 27.76 g of Li to atoms of Li?

• A

• B

• C

• D

Multiple Choice

What is the molar mass of table salt (NaCl)?

• 116.886 g/mol
• 35.453 g/mol
• 22.990 g/mol
• 58.443 g/mol

Multiple Choice

_P₄+_O₂ →  _P₂O₃

• 3 P₄+1 O₂ → 2 P₂O₃
• 1 P₄+1 O₂ → 2 P₂O₃
• 1 P₄+ 3 O₂ → 2 P₂O₃
• 1 P₄+ 2 O₂ → 3 P₂O₃

Multiple Choice

How many steps are in a gram to mole conversion?

• 1
• 2
• 3
• 4

Multiple Choice

What are the units for molar mass?

• grams
• amu
• grams/mole
• liters

Multiple Choice

What is the mass of one mole of silver?

• 32.06 g

• 107.87 g

• 14.01 g

• 22.99 g

Multiple Choice

Which conversion factor is best to solve this problem?

How many moles of CO₂ are in 16 grams of CO₂?

• 1 mole = 6.022x10²³ molecules

• 1 mole= molar mass (in grams)

• 1 mole= 22.4 Liters

• Coefficient(moles) of substance A = Coefficient(moles) of substance B

Multiple Choice

Which conversion factor is best to solve this problem?

How many moles of Carbon react with 6.0 moles of O₂?

• 1 mole = 6.022x10²³ molecules

• 1 mole= molar mass (in grams)

• 1 mole= 22.4 Liters

• Coefficient(moles) of substance A = Coefficient(moles) of substance B

Multiple Choice

Which conversion factor is best to solve this problem?

3.4 moles of a certain substance is equivalent to how many Liters?

• 1 mole = 6.022x10²³ molecules

• 1 mole= molar mass (in grams)

• 1 mole= 22.4 Liters

• Coefficient(moles) of substance A = Coefficient(moles) of substance B

Multiple Choice

Which conversion factor is best to solve this problem?

How many molecules are in 0.56 moles of Aluminum?

• 1 mole = 6.022x10²³ molecules

• 1 mole= molar mass (in grams)

• 1 mole= 22.4 Liters

• Coefficient(moles) of substance A = Coefficient(moles) of substance B

Multiple Choice

What is the correct setup for the following problem?

How many moles are in 12.4 grams of Helium?

• $12.4\ g\ He\ x\ \frac{4.003g\ He}{1\ mole\ He}$

• $12.4\ g\ He\ x\ \frac{1\ mole\ He}{4.003\ g\ He}$

• $4.003\ g\ He\ x\ \frac{12.4\ g\ He}{1\ mole\ He}$

• $4.003\ g\ He\ x\ \frac{1\ mole\ He}{12.4\ g\ He}$

Multiple Choice

What is the correct setup for the following problem?

How many molecules of Carbon are in 3.0 moles of Carbon?

•  $3.0\ mole\ C\ x\ \frac{6.022x10^{23}\ molecules\ C}{1\ mole\ C}$ 

•  $3.0\ mole\ C\ x\ \frac{1\ mole\ C}{6.022x10^{23}\ molecules\ C}$ 

•  $1\ mole\ C\ x\ \frac{3.0\ mole\ C}{6.022x10^{23}\ molecules\ C}$ 

•  $1\ mole\ C\ x\ \frac{6.022x10^{23}\ molecules\ C}{3.0\ mole\ C}$ 

Multiple Choice

What is the correct setup for the following problem?

How many moles are in 5.4 Liters of a substance?

•  $5.4\ L\ x\ \frac{1\ mole}{5.4\ L}$ 

•  $5.4\ L\ x\ \frac{1\ mole}{22.4\ L}$ 

•  $22.4\ L\ x\ \frac{1\ mole}{5.4\ L}$ 

•  $22.4\ L\ x\ \frac{5.4\ L}{1\ mole}$ 

Multiple Choice

Which conversion factor is best to solve this problem?

How many moles of CO₂ are in 16 grams of CO₂?

• 1 mole = 6.022x10²³ molecules

• 1 mole= molar mass (in grams)

• 1 mole= 22.4 Liters

• Coefficient(moles) of substance A = Coefficient(moles) of substance B

Multiple Choice

Which conversion factor is best to solve this problem?

How many moles of Carbon react with 6.0 moles of O₂?

• 1 mole = 6.022x10²³ molecules

• 1 mole= molar mass (in grams)

• 1 mole= 22.4 Liters

• Coefficient(moles) of substance A = Coefficient(moles) of substance B

Multiple Choice

Which conversion factor is best to solve this problem?

3.4 moles of a certain substance is equivalent to how many Liters?

• 1 mole = 6.022x10²³ molecules

• 1 mole= molar mass (in grams)

• 1 mole= 22.4 Liters

• Coefficient(moles) of substance A = Coefficient(moles) of substance B

Multiple Choice

What is the correct setup for the following problem?

How many moles are in 12.4 grams of Helium?

• $$12.4\ g\ He\ x\ \frac{4.003g\ He}{1\ mole\ He}$$

• $$12.4\ g\ He\ x\ \frac{1\ mole\ He}{4.003\ g\ He}$$

• $$4.003\ g\ He\ x\ \frac{12.4\ g\ He}{1\ mole\ He}$$

• $$4.003\ g\ He\ x\ \frac{1\ mole\ He}{12.4\ g\ He}$$

Multiple Choice

What is the correct setup for the following problem?

How many molecules of Carbon are in 3.0 moles of Carbon?

• $$3.0\ mole\ C\ x\ \frac{6.022x10^{23}\ molecules\ C}{1\ mole\ C}$$

• $$3.0\ mole\ C\ x\ \frac{1\ mole\ C}{6.022x10^{23}\ molecules\ C}$$

• $$1\ mole\ C\ x\ \frac{3.0\ mole\ C}{6.022x10^{23}\ molecules\ C}$$

• $$1\ mole\ C\ x\ \frac{6.022x10^{23}\ molecules\ C}{3.0\ mole\ C}$$

Multiple Choice

What is the correct setup for the following problem?

How many moles are in 5.4 Liters of a substance?

• $$5.4\ L\ x\ \frac{1\ mole}{5.4\ L}$$

• $$5.4\ L\ x\ \frac{1\ mole}{22.4\ L}$$

• $$22.4\ L\ x\ \frac{1\ mole}{5.4\ L}$$

• $$22.4\ L\ x\ \frac{5.4\ L}{1\ mole}$$

Multiple Choice

What is the mass of 3.66 mol of N₂?

• 28 grams

• 0.13 grams

• 102.5 grams

• 51.24 grams

Multiple Choice

What is the number of atoms that are in 1.25 mol of O₂?

• 1.5 x 10²⁴ atoms

• 7.5 x 10²³ atoms

• 40 atoms

• none of the choices

Multiple Choice

What is Avogadro's Number? (measures molecules and atoms)

• 6.02 x 10²³

• 3.145

• it changes

• 1

Mass --> Mole Conversions

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Equation for Mass : Mole Conversins

NOTE : The videos attached use the attached format for units :

Molar Mass : gram mol^-1

^{This is EXACTLY the same as we have been using}

^{Gram Formula Mass : grams/mol}