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 chemical compound using symbols for the elements and numbers to indicate the quantity of each element.

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What does the subscript in a chemical formula indicate?

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The subscript in a chemical formula indicates the number of atoms of the element present in the molecule. For example, in H2O, the '2' indicates there are 2 hydrogen atoms.

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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 number of atoms of each element together. For example, in C6H12O6, there are 6 + 12 + 6 = 24 total atoms.

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What is the significance of parentheses in chemical formulas?

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Parentheses in chemical formulas indicate that the elements inside the parentheses are grouped together and may be multiplied by a subscript outside the parentheses. For example, in (CH3)2, there are 2 groups of CH3.

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How many hydrogen atoms are in the molecule C2H6?

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There are 6 hydrogen atoms in the molecule C2H6.

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What is the molecular formula for glucose?

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The molecular formula for glucose is C6H12O6.

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How many atoms of each element are in the formula Ca(OH)2?

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In Ca(OH)2, there is 1 Calcium atom, 2 Oxygen atoms, and 2 Hydrogen atoms.

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What is the difference between a molecular formula and an empirical formula?

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A molecular formula shows the actual number of atoms of each element in a molecule, while an empirical formula shows the simplest whole-number ratio of the elements.

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How many total atoms are in the formula C3H8?

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There are 3 + 8 = 11 total atoms in the formula C3H8.

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What does the formula H2O represent?

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The formula H2O represents water, which consists of 2 hydrogen atoms and 1 oxygen atom.