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Home Concept Builders Mole Molar Mass Help Help 1

Molar Mass - Questions 1 Help

A compound consists of two or more elements. Elements are represnted by elemental symbols. A chemical formula for a compound identifies the elemental symbols of the elements in the compound and the number of atoms of each element. Subscripts listed immediately following an elemental symbol or after a group of symbols inside of parenthesis provides information about the number of atoms of each element.

There are six groups of three questions (18 questions in all) in the first activity, titled Counting Atoms. Each question involves the same task. A chemical formula for a compound is given and the student must count the number of atoms of each element must be counted. An example question is shown below.
 

Version 1:

Counting the number of atoms of each element in a formula is a prerequisite skill to determining the molar mass. Count the number of atoms of each element in the formula Al2(SO4)3.

Help for Counting Atoms Activity

Counting the number of atoms of each element in a formula is a pre-requisite skill for determining the molar mass of a compound. Study the graphic below to learn how to interpret formulas and count the number of atoms of each element in the formula.
 


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