2022 CHEM FINAL REVIEW Average Atomic Mass

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What is average atomic mass?

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The weighted average of the masses of an element's isotopes, taking into account their relative abundances.

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How do you calculate average atomic mass?

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Multiply the mass of each isotope by its percent abundance (as a decimal), then sum these values.

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What is an isotope?

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Atoms of the same element that have different numbers of neutrons, resulting in different masses.

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What does percent abundance mean?

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The percentage of a particular isotope present in a sample of an element.

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If an element has two isotopes, how do you find the average atomic mass?

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(Mass of Isotope 1 * Percent Abundance 1) + (Mass of Isotope 2 * Percent Abundance 2) = Average Atomic Mass.

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What is the significance of the average atomic mass in chemistry?

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It helps predict how an element will behave in chemical reactions and is used in calculations involving moles.

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What is the average atomic mass of an element with isotopes of 75.23 amu (24.1%), 74.61 amu (48.7%), and 75.20 amu (27.2%)?

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74.92 amu.

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What is the incorrect statement about isotopes?

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The percent abundance of all isotopes is equal. Different color beans cannot represent isotope.

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What is the average atomic mass of an element with isotopes of 20.74 amu, 22.56 amu, and 24.31 amu?

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24.31 amu.

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What is the average atomic mass of an element with isotopes of 106.38649 amu, 111.91896 amu, and 107.8677 amu?

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107.8677 amu.