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3 years ago

Can someone pls help me with this question

Chemistry

1 answer:

artcher [175]3 years ago

5 0

Answer:

The answer to your question is 24.325

Explanation:

Data

Magnesium-24 Abundance = 78.70%

Magnesium-25 Abundance = 10.13%

Magnesium-26 Abundance = 11.17%

Process

1.- Convert the abundance to decimals

Magnesium-24 Abundance = 78.70/100 = 0.787

Magnesium-25 Abundance = 10.13/100 = 0.1013

Magnesium-26 Abundance = 11.17/100 = 0.1117

2.- Write an equation

Average atomic mass = (Atomic mass-1 x Abundance 1) + (Atomic mass 2 x

Abundance-2) + (Atomic mass 3 x Abundance 3)

3.- Substitution

Average atomic mass = (24 x 0.787) + (25 x 0.1013) + (26 x 0.1117)

4.- Simplification

Average atomic mass = 18.888 + 2.533 + 2.904

5.- Result

Average atomic mass = 24.325

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$p_{He}$ = partial pressure of helium

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