Stoichiometry and Gas Laws

This video tutorial covers stoichiometry, focusing on converting grams to liters of a gas. It explains the chemical equation involving calcium and phosphoric acid, and details the steps to convert grams to moles, use molar ratios, and finally convert moles to liters using molar volume. The tutorial concludes with a summary of the process, emphasizing the importance of understanding molar relationships in chemical reactions.

What is the main objective of the video tutorial?

• To discuss the uses of phosphoric acid.

• To learn how to convert grams to liters of a gas.

• To understand the properties of calcium.

• To explore the history of stoichiometry.

What does the chemical equation in the video involve?

• Hydrogen gas reacting with oxygen to form water.

• Calcium and phosphoric acid reacting to form calcium phosphate and hydrogen gas.

• Calcium reacting with water to form calcium hydroxide.

• Phosphoric acid decomposing into phosphorus and oxygen.

Why is it important to use molar relationships instead of gram relationships?

• Because molar relationships are easier to calculate.

• Because chemical reactions occur at the molecular level.

• Because grams are not a standard unit in chemistry.

• Because grams cannot be measured accurately.

What is the first step in converting grams to liters of a gas?

• Determine the temperature and pressure of the gas.

• Measure the volume of the gas directly.

• Convert grams to moles using molar mass.

• Calculate the density of the gas.

How many grams of phosphoric acid are used in the example calculation?

• 18.75 grams

• 20 grams

• 15 grams

• 25 grams

What is the molar mass of phosphoric acid used in the calculation?

• 98 grams per mole

• 100 grams per mole

• 90 grams per mole

• 110 grams per mole

What is the molar ratio of phosphoric acid to hydrogen gas in the reaction?

• 1:2

• 2:3

• 3:2

• 1:1

How many moles of hydrogen gas are produced from 0.191 moles of phosphoric acid?

• 0.287 moles

• 0.191 moles

• 0.150 moles

• 0.300 moles

What is the molar volume of a gas at standard temperature and pressure?

• 18 liters per mole

• 20 liters per mole

• 24 liters per mole

• 22.4 liters per mole

How many liters of hydrogen gas are produced from 0.287 moles of hydrogen gas?

• 5.00 liters

• 8.50 liters

• 6.42 liters

• 7.00 liters