General Knowledge - Chemistry - Discussion

Option A is correct using temp/molar mass.

H2:73/2 = 36.5,
CH4:300/16 = 18.45,
N2:1027/28 = 36.67,
O2:0/32 = 0.

H2 and N2 if we compare their masses hydrogen is the lightest.

I hope you will understand.

Step 1: Convert 'c to kelvin
Step 2:use formula speed= √(RT/M).

Keeping R constant in each case. By calculating, option 1 is correct.

Let's solve it step- by- step:

Formula for molecular speed ( root mean square speed, urms):

Urms=√3RT/M

R=universal gas constant.
T= temperature in Kelvin.
M= molar mass (in kg/mol).

Higher t/m-higher speed. So we need to compare T/M for each gas.

Given:

A. H2 at -73⁰C _T= -73+273=200 k,M(H2)=2 g/mol = 0.002 kg/mol.
B. CH4 at 300 K_M(CH4) = 16 g/mol = 0.016 kg/mol,
C. N2 at 1,027⁰C_T=1,027 + 273 = 1300 k, M(N2) = 28 g/mol = 0.028 kg/mol,
D. O2 at 0⁰C_T=0 + 273 = 273K, M(02) = 32 g/mol = 0.032 kg /mol.

Now calculate T/M roughly:

A: 200/0.002 = 100,000.
B: 300/0.016 = 1 8,750.
C.1300/0.028 = 46,429.
D.273/0.032 = 8,531.

Result

Highest value is 100,000 for A(H2 at -73⁰C).

Thus, the Answer: A. H2 at -73⁰C.

Here h2 is the lightest element and it also directly proportional to the temperature that's why A is the right answer.

Please explain the right answer clearly.

Hydrogen gas with higher temperature and lower molecular weight have higher molecular speed.

Among the given gases, hydrogen at 50°C has a maximum value of T/M and the highest speed. The correct option is A.

Please explain it more clearly.

According to me, the given answer A is correct.

I think hydrogen gas is right. The light one will move faster.

I agree with @Jeffrin.

V is directly proportional to T.

With the decrease in temperature, attraction between the hydrogen molecules take place which will limit the movements of particles. This leads to decrease in kinetic energy which results in less speed of molecules. Thus, option A is incorrect.