[Chemistry Class Notes] on Moles to Grams Formula Pdf for Exam

Moles and grams are units of measurement that provide information regarding the quantity of any given substance. A mole is a unit of determining the amount of substance. A mole is exactly defined as the number of 6.023 * 10[^{23}] particles which can be either atoms, molecules, ions or electrons. Hence, one mole of a substance will contain 6.023 * 10[^{23}] particles. The number that is used in the definition of moles is known as Avogadro’s number. Grams is also a unit used to measure the quantity of a substance. It is the standard unit of the CGS system of measurement. Also, grams per mole defines the molecular weight of a substance. Hence, moles to grams formula conversion is an important conversion in chemistry measurements.

How to Convert Moles to Grams?

Moles and grams, as said earlier, are standard units of amounts of measurements. Typically, substances react in a simple ratio of their moles. The amount of the substances is physically weighed in grams. The weight of a particular amount of a substance for a chemical reaction that will occur in stoichiometric ratios of moles is taken in grams according to the CGS system of measurement. Hence, the process of how to convert moles to grams can be done using the following steps:

• Note and determine the number of moles that are required. 

• Calculate the molar mass of a particular substance depending on the chemical formula

• Multiplication of both the above-obtained values will in turn give the mass in grams.

Thus, the moles to gram conversion formula or gram to moles conversion formula is given below:

Weight in grams = Number of moles ∗ Molar mass of the substance 

Normally the standard units of weight as per the SI system of classification is in kilograms which is a thousand times a single unit of a gram. 

Examples of How to Convert Moles to Grams

Example 1: For Hydrochloric Acid 1 Mole is Equal to How Many Grams of HCL?

Solution: HCl is hydrochloric acid. The constituent elements of HCl are Hydrogen and Chlorine. The atomic masses of the constituent elements are given below:

Hydrogen, H = 1, Chlorine, Cl = 35.5.

Hence, the molecular mass of the compound will be = Mass of Hydrogen + Mass of Chlorine = 1 + 35.5 = 36.5.

Therefore, the molecular weight in grams of 1 mole of HCl = (No. of moles of HCl)*(Mass of HCl) = 1*36.5 = 36.5 grams.

Thus, for hydrochloric acid, 1 mole is equal to 36.5 grams of HCl.

Example 2: How to Convert Grams to Moles of Carbon Dioxide When the Given Requirement is 4.5 Moles of Carbon Dioxide.

Solution: CO[_{2}] is carbon dioxide. The constituent elements of CO[_{2}] are Carbon and Oxygen. The atomic masses of the given constituent elements are:

Carbon, C = 12, Oxygen, O = 16.

Hence, the molecular mass of the compound will be = Mass of Carbon + Total Mass of Oxygen = 12 + 2*16 = 44.

Therefore, the molecular weight in grams of 1 mole of HCl = (No. of moles of HCl)*(Mass of HCl) = 4.5*44 = 198 grams.

Thus, for carbon dioxide, 1 mole is equal to 198 grams of CO[_{2}].