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4 years ago

Pleaseeee help meeee

Chemistry

1 answer:

dlinn [17]4 years ago

4 0

Answer:

5) 24.3 amu

6) 193 amu

7) 6.94 amu

Explanation:

The fractional abundance shows how many atoms of the element exist as a particular isotope with a certain mass.

To find the average, multiply the fractional abundance with the mass. All the fractional abundance should add up to 100%.

5) Average atomic mass of Mg

= 78.7%× 23.985 +10.13% ×24.986 +11.17% ×25.983

= 24.3 amu (3 s.f.)

6) Avg atomic mass

= 37.85% ×191 +62.42% ×193

= 193 amu (3 s.f.)

7) Avg atomic mass

= 7.59% ×6.015 +92.41% ×7.016

= 6.94 amu (3 s.f.)

*amu stands for atomic mass units

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We are given:

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3 years ago

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balu736 [363]

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