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At 400 K, the root mean square (Ims) spe...

At 400 K, the root mean square (Ims) speed ofa gas X(molecular weight=40) is equal to the most probable speed of gas Y at 60 K. The molecular weight of Y is

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The correct Answer is:
4

`u = sqrt((3RT)/(M))` and `alpha = sqrt((2RT))/(M)) , u_(x) = sqrt((3RT_(x))/(M_(x)))` and `alpha_(y) = sqrt((2RT_(y))/(M_(y)))`
As `u_(x) = alpha _(y) , therefore (3 RT_(x))/(M_(x)) = (2R T_(y))/(M_(y)) or M_(y) = (2 T_(y) )/(3 T_(x)) xx M_(x) = (2)/(3) xx (60)/(400) xx 40 = 4`
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Knowledge Check

  • The root mean square velocity of the molecules of a gas is 1260m//s The most probable speed of the molecules is:

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