Molar Mass

Molar mass is a measurement of the mass of a given substance. It is defined as the mass of one mole of a substance and is expressed in grams per mole (g/mol). Molar mass is an important concept in chemistry as it allows us to convert between the mass of a substance and the number of moles of that substance.

Calculating Molar Mass

The molar mass of a substance is calculated by adding up the atomic masses of all the atoms present in the molecular formula of the substance. The atomic mass of an element is found on the periodic table and is usually expressed in atomic mass units (u) or grams per mole (g/mol).

For example, the molar mass of water, H₂O, can be calculated as follows:

2(1.00794 u) + 15.9994 u = 18.01528 u

So, the molar mass of water is approximately 18.01528 g/mol.

Using Molar Mass

Molar mass is used in a variety of calculations in chemistry. It is used to convert between the mass of a substance and the number of moles of that substance using the formula:

moles = mass / molar mass

It is also used to calculate the mass percent composition of a compound, as well as in stoichiometry calculations to determine the amount of products formed in a chemical reaction.

Study Guide

1. What is molar mass and how is it defined?
2. How is molar mass calculated?
3. What is the molar mass of water? Show your calculation.
4. How is molar mass used in chemistry calculations?
5. Give an example of a calculation using molar mass.

Understanding molar mass is essential for any student studying chemistry. It is a fundamental concept that is used in a wide range of chemical calculations and provides a basis for understanding the quantitative aspects of chemical reactions and compositions.

[Molar Mass] Related Worksheets and Study Guides:

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