Chemical Formulas

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What is a chemical formula?

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A chemical formula is a way of expressing information about the proportions of atoms that constitute a particular chemical compound or molecule.

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

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The number of atoms of an element in a chemical formula is indicated by the subscript next to the element's symbol. If there is no subscript, it means there is one atom of that element.

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What is the difference between a chemical change and a physical change?

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A chemical change results in the formation of new substances with different properties, while a physical change does not alter the chemical composition of a substance.

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What are the products of the reaction NH3 -> N2 + H2?

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The products of the reaction are nitrogen gas (N2) and hydrogen gas (H2).

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How many different elements are present in the compound C6H12O6?

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There are three different elements present in C6H12O6: carbon (C), hydrogen (H), and oxygen (O).

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What does the subscript in a chemical formula represent?

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The subscript in a chemical formula represents the number of atoms of the element in one molecule of the compound.

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What is the significance of balancing chemical equations?

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Balancing chemical equations is important because it ensures that the law of conservation of mass is obeyed, meaning that the number of atoms of each element is the same on both sides of the equation.

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What is an example of a physical change?

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An example of a physical change is water evaporating, as it changes from liquid to gas but remains H2O.

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How many phosphorus atoms are in the compound H3PO4?

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There is one phosphorus atom in the compound H3PO4.

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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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