Stoichiometry Pre-test

• 1

• 2

• 3

• 4

Tags

NGSS.MS-PS1-1

What is the total number of atoms in this formula: CaCl₂

• 2

• 4

• 3

• 1

Tags

NGSS.MS-PS1-1

What is the total number of atoms in 4H₂O?

Tags

NGSS.MS-PS1-1

What is the molar mass of NaOH?

• 40 g/mol
• 31 g/mol

• 23.998 g/mol
• 20 g/mol

What is the molar mass of 2CO₂?

• 64

• 88

• 32
• 44

What is the correct molar mass for Mg(OH)₂? (Round to two decimal places)

Calculate the molar mass of NH₄NO₂. Round to the nearest whole number.

Where does the mole ratio come 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

Tags

NGSS.HS-PS1-7

4 NH₃ + 5 O₂ → 4 NO + 6 H₂O

What is the mole ratio of oxygen to water? (a)  

What is the mole ratio of NH₃ to NO? ​ (b)  

What is the mole ratio of NH₃ to oxygen? ​ (c)  

What is the mole ratio of H₂O to NH₃? ​ (d)  

• 6/5
• 4/4
• 4/5
• 6/4
• 4/6
• 5/6
• 5/4
• 6/6

Tags

NGSS.HS-PS1-7

4 FeS + 7 O₂ → 2 Fe₂O₃ + 4 SO₂

Place the numbers in the correct spots to solve this problem: how many moles of FeS will be needed to produce 13.72 moles of Fe₂O₃? (end amount is the answer)

g

h

i

e

7 mol O₂

13.72 mol FeS

4 mol FeS

2 mol Fe₂O₃

27.44 mol FeS

4 mol Fe₂O₃

4 mol SO₂

2 mol FeS

13.72 mol Fe₂O₃

6.86 mol FeS

Tags

NGSS.HS-PS1-7