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3 years ago

6

The atomic masses of the two stable isotopes of boron; boron-10 (natural abundance:19.78%) and boron-11 (natural abundance:80.22

%) are 10.0129 amu and 11.0093 amu, respectively. calculate the average atomic mass of boron
10.41 amu
10.95 amu
10.81 amu
10.72 amu
10.13 amu

1 answer:

iogann1982 [59]3 years ago

5 0

(19.78 x 10) + (80.22 x 11) all of them divided by 100= 10.81 amu

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<h3>Data obtained from the question </h3>

Initial temperature (T₁) = 149.05 °C = 149.05 + 273 = 422.05 K
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The new temperature of the gas can be obtained by using the combined gas equation as illustrated below:

P₁V₁ / T₁ = P₂V₂ / T₂

Since the volume is constant, we have:

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349.84 / 422.05 = 103.45 / T₂

Cross multiply

349.84 × T₂ = 103.45 × 422.05

Divide both side by 349.84

T₂ = (103.45 × 422.05) / 349.84

T₂ = 124.80 K

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