Counting Atoms

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What is a chemical change?

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A chemical change is a process where one or more substances are transformed into different substances with new chemical properties. Examples include burning paper, rusting iron, and baking a cake.

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What is a physical change?

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A physical change is a change that affects one or more physical properties of a substance without altering its chemical composition. Examples include cutting, folding, or tearing paper.

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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 only one atom of that element.

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What does the subscript in a chemical formula represent?

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The subscript in a chemical formula indicates the number of atoms of the element that precedes it. For example, in H2O, the '2' indicates there are two hydrogen atoms.

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How many atoms of Carbon are in C3H5(NO3)3?

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There are 3 atoms of Carbon in C3H5(NO3)3.

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How many atoms of Nitrogen are in C3H5(NO3)3?

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There are 3 atoms of Nitrogen in C3H5(NO3)3.

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How many atoms of Oxygen are in C3H5(NO3)3?

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There are 9 atoms of Oxygen in C3H5(NO3)3.

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What is the total number of atoms in C3H5(NO3)3?

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The total number of atoms in C3H5(NO3)3 is 20 (3 Carbon + 5 Hydrogen + 3 Nitrogen + 9 Oxygen).

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What is rusting an example of?

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Rusting is an example of a chemical change.

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What happens to the properties of a substance during a chemical change?

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During a chemical change, the properties of the original substance change, and new substances with different properties are formed.