Use the data given in the following table to calculate the molar mass of naturally occurring argon isotopes:

 Isotope Molar mass Abundance $$\, _{ 36 }\textrm{Ar}$$ $$35.96755 g \; mol^{ -1 }$$ 0.337 % $$\, _{ 38 }\textrm{Ar}$$ $$37.96272 g \; mol^{ -1 }$$ 0.063 % $$\, _{ 40 }\textrm{Ar}$$ $$39.9624g \; mol^{ -1 }$$ 99.600 %

Asked by Abhisek | 1 year ago |  135

##### Solution :-

Molar mass of Argon:

$$( 35.96755 \; \times \; \dfrac{ 0.337 }{ 100 }) +( 37.96272 \; \times \; \dfrac{ 0.063 }{ 100 })$$

$$+ 39.9624 \; \times \; \dfrac{ 99.600 }{ 100 })$$

= [0.121 + 0.024 + 39.802] $$g \; mol^{ -1 }$$

= 39.947$$g \; mol^{ -1 }$$

Answered by Pragya Singh | 1 year ago

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