General Knowledge - Chemistry - Discussion

Nomally Hydrogen is a vey litgt gas.

B is right, because methane is very lightest gas and having fastest speed.

Speed of molecules in gases is dirctly proportional to tempurature n inversely to its mass as per kinetic theroy and only A satisfies the above condition.

The answer is only (A) the correct explanation is given by @Chemistry Nepal.

The speed of the gaseous molecules is inversely proportionally to their molecular mass. In this case hydrogen satisfy this condition.

CH4 IS THE ANSWER TO THE QUESTION BECAUSE.

Average speed = Square root of (8RT/pi M).

T = Temperature.

Pi = 22/7 or 3.14.

M = molecular mass.

Now since mass is in denominator. It means molecular mass is inversely proportional to average speed. So as mass increases average speed decreases. And as mass decreases average speed increases.

So find out which of the following has lightest molecular mass?

CH4 = 16 g/mole.

Kr = 83.8 g/mole.

N2 = 28 g/mole.

CO2 = 44 g/mole.

Ar = 39.9 g/mole.

Since CH4 has lowest molecular mass among these so it's average speed will be highest.

Lighter mass and high temperature both are taken into account. So answer is A.

Answer A is right.

Because hydrogen is the lightest gas.

Obviously hydrogen is very light gas.

There are two factors weight and temperature.

Root mean square velocity = 3RT/M.