Counting Atoms in Chemical Formulas

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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 do subscripts in a chemical formula indicate?

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Subscripts indicate the number of atoms of the element in a molecule. For example, in H2O, the '2' indicates there are two hydrogen atoms.

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What is a coefficient in a chemical equation?

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A coefficient is a number placed in front of a chemical formula to indicate how many molecules or moles of that substance are present.

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

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To find the total number of atoms, add up all the atoms represented by the elements in the formula, taking into account the subscripts.

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What is the difference between an element and a compound?

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An element is a pure substance made of only one type of atom, while a compound is a substance formed when two or more different types of atoms bond together.

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How many total atoms are in C6H12O6?

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There are 24 total atoms in C6H12O6 (6 Carbon + 12 Hydrogen + 6 Oxygen = 24).

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What does the formula 2Al2O3 represent?

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The formula 2Al2O3 represents 2 molecules of aluminum oxide, which contains a total of 4 aluminum atoms and 6 oxygen atoms.

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What is the significance of the number in front of a chemical formula?

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The number in front of a chemical formula (coefficient) indicates how many molecules of that compound are present in a reaction.

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In the formula C2H8O, how many oxygen atoms are present?

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There is 1 oxygen atom present in the formula C2H8O.

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What is the role of coefficients in balancing chemical equations?

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Coefficients are used to balance chemical equations by ensuring that the number of atoms for each element is the same on both sides of the equation.