Chemistry Problems

There are many molecules and atoms in a drop of water. — Have you ever wondered how many molecules or atoms are in a drop of water? This is a common chemistry problem students solve because it deals with several important concepts, including chemical formulas, unit conversions, volume, mass, density, using the periodic table, the mole, and Avogadro’s number. Here is a […]

How Many Molecules and Atoms in a Drop of Water?

This entry was posted on March 12, 2020 by Anne Helmenstine (updated on August 17, 2022)

Gas Tank for Density of Ideal Gas Example — A common homework problem involving the ideal gas law is finding the density of an ideal gas. The idea of the problem is to bring in previously learned concepts of density and molecular mass into problems involving mostly pressures, volumes, and temperatures. This example problem will show how to find […]

Density of an Ideal Gas Example Problem – How to ...

This entry was posted on July 11, 2018 by Todd Helmenstine (updated on February 8, 2022)

Grams to Moles — Converting grams to moles is a common chemistry problem. Usually, you see it when you know the mass of a substance, but not the balanced equation for the reaction. These two example problems show the best way to convert grams to moles and moles to grams of a molecule. Grams to […]

Converting Grams to Moles Example Problem – Convert g to ...

This entry was posted on September 26, 2017 by Todd Helmenstine (updated on August 7, 2022)

magnesium boron — Atomic mass is the combined mass of all the protons, neutrons, and electrons that make up an atom. Electrons have nearly 1/2000th of the mass of protons and neutrons, so electrons are typically ignored in calculations involving atomic mass. This means the atomic mass is the sum of the masses […]

How to Find Atomic Mass – Calculate Atomic Mass Example ...

This entry was posted on September 19, 2017 by Todd Helmenstine (updated on May 17, 2021)

Hess's Law Example Problem Abstract Energy Cube — Hess’s law of constant heat summation, or Hess’s law for short is a relationship describing the enthalpy change of a reaction. The total enthalpy change of a reaction is the sum of total enthalpies for each step of the reaction and is independent of the order of the steps. Basically, […]

Hess’s Law Example Problem

This entry was posted on August 6, 2017 by Todd Helmenstine (updated on November 28, 2021)

Phosphoric acid is an example of an oxoacid. (Ben Mills) — An oxoacid is a type of acid that contains oxygen bonded to hydrogen and another element. This chemistry example problem explains how to identify the strongest acid from a list of oxoacids, also known as oxyacids. Oxoacid Example Problem Which of the following is the strongest acid? HClO4 HClO3 HClO2 […]

Oxoacid Example Chemistry Problem

This entry was posted on March 27, 2017 by Anne Helmenstine (updated on May 17, 2021)

Boyle's Law describes the relationship between pressure and volume of a gas when mass and temperature are held constant. (NASA) — Boyle’s Law is a special case of the ideal gas law in which the pressure and volume of an ideal gas are inversely proportional to each other, providing the temperature and mass of the gas are held constant. Here’s an example of how to perform a calculation using Boyle’s Law. […]

Boyle’s Law Example Problem

This entry was posted on January 25, 2017 by Anne Helmenstine (updated on February 8, 2022)

Ammonia Ball and Stick Model — Many chemical reactions take place until one of the reactants run out. This reactant is known as the limiting reactant. Often it is straightforward to determine which reactant will be the limiting reactant, but sometimes it takes a few extra steps. Consider, for example, burning propane in a grill. The […]

How to Find the Limiting Reactant – Limiting Reactant Example

This entry was posted on October 7, 2016 by Todd Helmenstine (updated on September 4, 2022)

How to Calculate Theoretical Yield — Learn how to calculate theoretical yield. The theoretical yield of a reaction is the amount of product expected from a chemical reaction.

How to Calculate Theoretical Yield – Definition and Example

This entry was posted on October 5, 2016 by Todd Helmenstine (updated on August 7, 2022)