Moving from Single Step Mole Conversions into Double Step

Moving from Single Step Mole Conversions into Double Step

Single Step Mole Conversions

• Going from grams to moles (or moles to grams) -- involves formula mass (aka molar mass)

• Going from volume to moles (or moles to volume) -- involves 22.4 L of gas at STP (Standard Temperature and Pressure 0 deg Celsius and 1 atmosphere)

• Going from particles to moles (or moles to particles) -- involves Avagadro's number

Multiple Choice

How many moles are in a 18 L tank of nitrogen gas?

• 0.9 moles

• 1 mole

• 0.8 moles

• 0.75 moles

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

Determine the mass of 4.20 moles of C₆H₁₂

• 353 g

• 0.0499 g

• 337 g

• 2.53 x 10²⁴ g

Multiple Choice

How many molecules are there in 31.8 moles of water?

• 5.28 x 10^-23 molecules

• 1.91 x 10²⁵ molecules

• 5.28x 10-²⁵

• 1.91 x 10²²

Multiple Choice

What is the molar mass of PbSO₄?

• 303.27 g/mol

• 255.27 g/mol

• 163.87 g/mol

• 372.27 g/mol

Multiple Choice

The mass of one mole of an element is equal to

• its atomic number from the periodic table, but in amus.

• its atomic mass from the periodic table, but in amus.

• its atomic mass from the periodic table, but in grams.

• its atomic number from the periodic table, but in grams.

Double Step (or MultiStep) Mole Conversions

• Can be broken down into multiple single steps

• You can do multiple steps using one substance A and go from grams to mole to L or L to moles to particles or you can do multiple steps using two substances.

• For multiple steps, use the steps below: Step 1: Get to moles of A from wherever you are

• Step 2: Use mole ratio to go from moles of A to moles of B

• Step 3: Go from moles of B to the answer of the question by using the proper process to go to grams, liters, or particles of B (depending on what the question asks)

Double Step Conversion Example

• How many particles of Na are in 45 g Na

• Step 1: Go from g Na to moles of Na 45/22.99 = 1.95737 moles Na

• Step 2: Go from moles Na to atoms Na = 1.95737 moles * (6.02 x 10²³ atoms Na) = 1.178338 x 10²⁴ atoms Na = 1.18 x 10²⁴ atoms Na

Multiple Choice

How many moles of NH₃ are produced when 6.8 g of H₂ are used in the reaction provided?

• 27.2 moles NH₃

• 2 moles NH₃

• 4.53 moles NH₃

• 2.27 moles NH₃

Multiple Choice

How many moles of zinc (II) chloride are produced from the reaction of 80 g of zinc?

• 5.23 x 10³ moles ZnCl₂

• 0.81 moles ZnCl₂

• 1.22 moles ZnCl₂

• 80 moles ZnCl₂

Multiple Choice

How many moles of Aluminum Phosphate (AlPO₄) are produced when 250 grams of Aluminum Nitrate (Al(NO₃)₃ react?

• 1.17 moles AlPO₄

• 5.32 x 10⁴ moles AlPO₄

• 250 moles AlPO₄

• 0.85 moles AlPO₄

Multiple Choice

How many moles of oxygen are necessary to react completely with 4.0 moles of propane (C₃H₈)?

• 12 moles O₂

• 1.33 moles O₂

• 0.75 moles O₂

• 3 moles O₂

Multiple Choice

How many moles of hydrogen, H₂, are needed to react with 2.0 moles of nitrogen, N₂?

• 3 moles H₂

• 0.66 moles H₂

• 6 moles of H₂

• 1.5 moles H₂

Multiple Choice

The middle conversion factor is the

• mole ratio of C₂H₁₈ to CO₂

• molar mass of CO₂

• molar mass of O₂

• combination lock of your locker

Multiple Choice

When converting from gram to gram, how many steps are there

• 1

• 2

• 3

• 4

Multiple Choice

Converting from gram A to gram B, the first step is to

• Convert from mole A to mole B

• Convert from mole B to gram B

• Convert from gram A to mole A

Multiple Choice

How many steps are in a gram to molecule conversion?

• 1

• 2

• 3

• 4

Multiple Choice

How many molecules are in 3.6 grams of NaCl?

• 0.06

• 1.0x10²¹

• 1.3x10²⁶

• 3.7x10²²

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

How many grams are in 1.2 x 10²⁴ molecules of CO?

• 28 grams
• 56 grams
• 6.02 grams
• 1.2 grams