Chemical Formulas and Counting Atoms

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What is a chemical formula?

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A chemical formula is a way of expressing the composition of a substance using symbols for its constituent elements and numbers to indicate the quantity of each element.

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What does a coefficient in a chemical formula represent?

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A coefficient represents the number of molecules or formula units of a substance in a chemical reaction.

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What is a subscript in a chemical formula?

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A subscript is a small number written to the right of a chemical symbol that indicates the number of atoms of that element in a molecule.

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How many atoms are in the formula H2O?

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There are 3 atoms in the formula H2O (2 hydrogen atoms and 1 oxygen atom).

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What does the formula CaO represent?

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The formula CaO represents calcium oxide, which consists of one calcium atom and one oxygen atom.

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How do you determine the total number of atoms in a chemical formula?

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To determine the total number of atoms, add the numbers indicated by the subscripts for each element in the formula.

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What is the difference between a coefficient and a subscript?

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A coefficient indicates the number of molecules, while a subscript indicates the number of atoms of an element in a molecule.

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In the formula 3H2SO4, how many sulfur atoms are present?

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There are 3 sulfur atoms in the formula 3H2SO4.

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What is the total number of atoms in the formula C6H12O6?

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There are 24 atoms in the formula C6H12O6 (6 carbon, 12 hydrogen, and 6 oxygen).

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What does the formula NaCl represent?

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The formula NaCl represents sodium chloride, which consists of one sodium atom and one chlorine atom.