Moles, Mass, and Volume Stoichiometry

What is the molar mass of (NH₄)₂CO₃ ?

• 144 g
• 138 g
• 96 g
• 78 g

In the equation 2 Al₂O₃ → 4 Al + 3 O₂, what is the mole ratio (coefficients) between the products aluminium and oxygen?

• 10:6

• 4:6

• 4:3

• 2:3

Tags

NGSS.HS-PS1-7

Balance this equation: ____ RbNO₃ + ____ BeF₂ → ____ Be(NO₃)₂ + ____ RbF

• 1:1:1:1

• 1:2:1:1

• 2:1:1:2

• 2:1:2:1

The first step when trying to solve a stoichiometry problem (mole problem) is to...

• write a balanced equation

• convert grams to moles

• convert grams to decimetres cubed

• use the mole ratio

2H₂ + O₂ → 2H₂O

How many moles of water can be produced if 4 moles O₂ react with excess hydrogen?

• 4 moles

• 8 moles

• 16 moles

• 2 moles

Tags

NGSS.HS-PS1-7

What is the mass of 7.8 moles of NaCl to the nearest whole number?

• 455 g

• 456 g

• 457 g

For the balanced equation, 3 Mg + 1 Fe₂O₃ → 3 MgO + 2 Fe, what is the mole ratio between magnesium oxide and iron?

• 6 : 2

• 2 : 3

• 1 : 2

• 3 : 2

Tags

NGSS.HS-PS1-7

A chamber of chlorine gas contains 1.4 dm³ of gas at RTP.

2 Na + Cl₂ → 2 NaCl

How many moles of sodium metal are needed to react completely with all of the chlorine to form NaCl?

• 0.12 moles (2 s.f.)

• 0.039 moles (2 s.f.)

• 0.029 moles (2 s.f.)

• 2.8 moles (2 s.f.)

What is the volume occupied by 1 mole of any gas at RTP?

• 44.8 dm³

• 24.0 dm³

• 16.8 dm³

• 22.4 dm³

What is the volume of 2 moles of helium gas at RTP?

• 48.0 dm³

• 24.0 dm³

• 12.0 dm³

• 96.0 dm³