Target Stoichiometry Lab with Baking Soda

Target
Stoichiometry
Lab

The purpose of this lab is to practice simple stoichiometry concepts.

Multiple Choice

Which has more moles of particles?

• 12.0 g carbon

• 6.94 g lithium

• 10.81 g boron

• all have the same number of moles

Multiple Choice

How many moles is in 25.0 g of calcium?

• 25.0 moles

• 0.62 moles

• 1.60 moles

• 40.0 moles

Multiple Choice

Determine the number of moles in 25.0 grams of potassium sulfide (K₂S).

• 0.23 moles

• 4.41 moles

• 110.3 moles

• 25.0 moles

Multiple Choice

Determine the number of moles in 1.50 grams of copper metal.

• 1.50 grams

• 0.023 moles

• 42.4 moles

• 6.02x10²³

Multiple Choice

Which weighs more?

• 1 mole of lithium

• 1 moles of carbon

• 1 mole of sodium

• 1 mole of silicon

Multiple Choice

What is the mass of 0.25 moles of rubidium bromide (RbBr)?

• 165.34 g

• 0.25 g

• 41.3 g

• 0.024 g

Multiple Choice

How many moles are in 30.0 grams of silicon dioxide (SiO₂)

• 60.1 moles

• 30.0 moles

• 0.50 moles

• 2.00 moles

Multiple Choice

If you had 20.0 g of each of the following, which would have the most moles?

• LiCl

• NaCl

• KCl

• RbCl

Multiple Choice

How many grams does 0.50 moles of silicon dioxide (SiO₂) weigh?

• 2.0 g

• 0.50 g

• 60.1 g

• 30.0 g

Multiple Choice

What is the molar mass of copper sulfate (CuSO₄)?

• 159.6 g/mole

• 111.6 g/mol

• 77.0 g/mol

• none of these

Multiple Choice

How many moles is in 8.40 grams of cobalt(II) nitrate, Co(NO₃)₂.

• 182.9 moles

• 8.40 moles

• 0.0459moles

• 21.77 moles

Multiple Choice

How many moles are in 0.75 grams of potassium permanganate (KMnO₄)?

• 0.75 moles

• 118.5 moles

• 0.0047 moles

• 0.0084 moles

Multiple Choice

What is the mass of 0.75 moles of potassium permanganate (KMnO₄)?

• 0.75 g

• 118.5 g

• 82.5 g

• 0.0084 g

Multiple Choice

How many grams are in 0.84 moles of cobalt(II) nitrate, Co(NO₃)₂.

• 182.9 g

• 8.40 g

• 153.6 g

• 0.00065 g

Multiple Choice

How many moles of zinc are in 15.0 grams of zinc sulfide (ZnS)?

• 65.38 moles

• 10.1 moles

• 0.15 moles

• 15.0 moles

Multiple Choice

What is the ratio of red apples to green apples

• 7 apples to 3 green

• 4 red apples to 7 apples

• 4 red apples to 3 green apples

• 3 green apples to 4 red apples

Multiple Choice

If there are 5 boys and 7 girls, write the ratio of girls to boys.

• 5 to 7
• 7 to 5
• 5 to 12
• 7 to 12

Multiple Choice

N₂ +  3H₂ → 2NH₃ 
What is the mole ratio between Nitrogen and Ammonium in the above reaction?

• 1 moles NH₃ / 2 moles N₂ 

• 3 moles NH₃ / 1 moles N₂ 

• 2 moles N₂ / 2 moles NH₃ 

• 1 moles N₂ / 2 moles NH₃ 

Multiple Choice

4 FeS + 7 O₂ → 2 Fe₂O₃ + 4 SO₂

What is the mole ratio of iron sulfide to oxygen gas?

• 4/7

• 7/4

• 2/7

• 7/2

Multiple Choice

3 Hg(OH)₂ + 2 H₃PO₄ → Hg₃(PO₄)₂ + 6 H₂O

What is the mole ratio of Hg₃(PO₄)₂ to H₃PO₄?

• 1 to 2

• 2 to 1

• 2 to 3

• 3 to 2

Multiple Choice

3 Hg(OH)₂ + 2 H₃PO₄ → Hg₃(PO₄)₂ + 6 H₂O

What is the mole ratio of Hg(OH)₂ to Hg₃(PO₄)₂ ?

• 1 to 2

• 2 to 1

• 3 to 1

• 1 to 3

Multiple Choice

Mole Ratios used for conversions are derived from:

• the molar mass of the reactants in the balanced chemical equation

• the coefficients of the balanced chemical equation

• the subscripts of the products in the balanced chemical equation

• the group number of each element in the balanced chemical equation

Multiple Choice

In the equation 2 Al₂O₃ → 4 Al + 3 O₂, what is the mole ratio of aluminum to oxygen?

• 10:6 
• 3:4
• 4:3
• 2:3

Multiple Choice

N₂ +  3H₂ → 2NH₃ 
What is the mole ratio between Nitrogen and Ammonium in the above reaction?

• 1 moles NH₃ / 2 moles N₂ 

• 3 moles NH₃ / 1 moles N₂ 

• 2 moles N₂ / 2 moles NH₃ 

• 1 moles N₂ / 2 moles NH₃ 

Multiple Choice

2Na + S → Na₂S

What is the ratio of Na₂S to Na?

• 1:1

• 1:2

• 2:1

• 2:2

Open Ended

Mass a clean dry test tube and record the mass of the empty test tube. Once this is done, add a scoop of sodium hydrogen carbonate (baking soda) to your test tube and mass it again. Record both the mass of the empty test tube and the starting mass here and on a piece of paper that will be turned in when the lab is over to show all your work.

Video Response

Take a short video of your test tube being gently heated by a cool flame on the bunsen burner. Be sure to show the condensation on the glass as well as the color of the litmus paper indicating a weak acid in the gases being emitted.

Open Video Recorder

Open Ended

Once your test tube is no longer emitting water and it begins to look more grayish in color.... about 5 minutes under the flame, let your test tube cool for another 5 minutes and then mass it again on your same scale to determine the mass of the new product (sodium carbonate) Write your ending mass here as well as on your paper.

Draw

Now that you have your starting mass and your ending mass, take this slide to write out your balanced equation and then show how to convert from grams of sodium hydrogen carbonate to grams of sodium carbonate.

step 1: write a balanced equation

step 2: set up a dimensional analysis problem that uses molar masses and mole ratios to solve this problem

Open Ended

how close was your calculated mass of sodium carbonate to your real mass of sodium carbonate?

calculate your percent error here and discuss why you think it was the value it is

calculated number - actual number/ actual number X 100= percent error