Stoichiometry

Front

What is Stoichiometry?

Back

Stoichiometry is the branch of chemistry that deals with the calculation of reactants and products in chemical reactions based on the conservation of mass.

Front

What is the mole concept?

Back

The mole is a unit of measurement in chemistry that represents 6.022 x 10²³ particles (atoms, molecules, ions, etc.). It allows chemists to count quantities of substances.

Front

What is the balanced equation for the reaction of ammonia and nitrogen monoxide?

Back

4NH₃ + 6NO → 5N₂ + 6H₂O.

Front

How do you determine the volume of gas produced in a reaction at STP?

Back

At STP (Standard Temperature and Pressure), 1 mole of any gas occupies 22.4 liters. Use stoichiometry to convert moles to liters.

Front

What is the relationship between moles of reactants and products in a balanced equation?

Back

The coefficients in a balanced chemical equation represent the ratio of moles of reactants to moles of products.

Front

How do you convert grams to moles?

Back

To convert grams to moles, divide the mass of the substance by its molar mass (grams/molar mass = moles).

Front

What is the molar mass of potassium bromide (KBr)?

Back

The molar mass of KBr is approximately 119 g/mol (39 g/mol for K and 80 g/mol for Br).

Front

How many moles of Fe can be produced from 3 moles of Fe₂O₃?

Back

6 moles of Fe can be produced from 3 moles of Fe₂O₃ according to the equation: Fe₂O₃ + 3H₂ → 2Fe + 3H₂O.

Front

What is the mass of O₂ needed to burn 36.1 g of B₂H₆?

Back

124 g of O₂ is needed to burn 36.1 g of B₂H₆ according to the reaction: B₂H₆ + 3O₂ → 2HBO₂ + 2H₂O.

Front

How do you calculate the grams of a product formed in a reaction?

Back

Use stoichiometry: convert moles of reactant to moles of product using the balanced equation, then convert moles of product to grams.