Mole Questions

Read each question and choose the best answer. You were given a set of four test tubes. Each test tube contains 100 g sample of the following elements. If the elements are all monoatomic, which test tube contains the largest number of moles?

• Carbon

• Potassium

• Sodium

• Iron

Read each question and choose the best answer.

The atomic number of oxygen is 8. The atomic number of sulfur is 16. Compared with a mole of oxygen, a mole of sulfur contains

• twice as many atoms

• half as many atoms

• an equal number of atoms

• 8 times as many atoms

Given the balanced equation representing a reaction:
H2 + energy ---> H + H
What occurs as bonds are broken in one mole of H2 molecules during this reaction?

• Energy is absorbed and one mole of unbonded hydrogen atoms is produced.

• Energy is absorbed and two moles of unbonded hydrogen atoms are produced.

• Energy is released and one mole of unbonded hydrogen atoms is produced.

• Energy is released and two moles of unbonded hydrogen atoms are produced.

Tags

NGSS.HS-PS1-4

If an equation is balanced properly, both sides of the equation must have the same number of

• atoms

• coefficients

• molecules

• moles of molecules

Tags

NGSS.HS-PS1-7

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

2 C₂H₆ + 7 O₂ → 4 CO₂ + 6 H₂O

Ethane (C₂H₆) combusts in the above reaction. What is the mole ratio of ethane to oxygen gas?

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2 C₂H₆ + 7 O₂ → 4 CO₂ + 6 H₂O

Ethane (C₂H₆) combusts in the above reaction. What is the mole ratio of carbon dioxide to water?

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Tags

NGSS.HS-PS1-7

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

Tags

NGSS.HS-PS1-7

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 

What is the mole ratio of water to oxygen?

• 4/4

• 4/5

• 6/4

• 6/5

Tags

NGSS.MS-PS1-5