Stoichiometry

What unit is used to measure the number of particles in a substance?

• kilogram

• mole

• Liter

• dozen

How many oxygen atoms are in 5 molecules of Mohr's salt: (NH₄)₂Fe(SO₄)₂?

• 6

• 8

• 20

• 40

Tags

NGSS.HS-PS1-7

A sealed container of nitrogen gas contains 6 × 10²³ molecules at STP. As the temperature increases, the mass of the nitrogen will

• increase.

• decrease.

• remain the same.

Tags

NGSS.HS-PS1-7

At STP, 32.0 g of O₂ would occupy the same volume as

• 64 g of H₂

• 4.0 g of He

• 12.0 g of CH₄

• 7.0 g of N₂

At STP, what mass of CH₄ has the same number of molecules as 18.0 grams of H₂O?

• 18.0 g

• 7.0 g

• 10.0 g

• 16.0 g

Tags

NGSS.HS-PS1-7

The atomic masses of any two elements contain the same number of ____.

• atoms

• grams

• Liters

• molecules

Tags

NGSS.HS-PS1-7

Which mass contains 6.02 × 10²³ atoms?

• 6.0 g of carbon

• 3.0 g of helium

• 28.0 g of silicon

• 16.0 g of sulfur

Tags

NGSS.HS-PS1-7

Which represents the greatest mass?

• 1 mole of argon

• 1 molecule of argon

• 1 gram of argon

• 1 atom of argon

What is the total number of molecules contained in 0.50 mole of O₂ at STP?

• 3.01 × 10²³

• 6.02 × 10²³

• 4.5 × 10²³

• 1.5 × 10²³

Tags

NGSS.HS-PS1-7

Given the reaction:

2 CO + O₂ → 2 CO₂

What is the minimum number of moles of O₂ required to produce one mole of CO₂?

• 0.25

• 2.0

• 0.50

• 1.0

Tags

NGSS.HS-PS1-7