Amixture of two gases was allowed to effuse from a container. one of the gases escaped from the container 1.43 times as fast as the other one. the two gases could have been:

C. Cl2 and SF6

Explanation:

Therefore, in this case we need two gases that have a ratio of their rates of diffusion as 1.43.

Thus; For Cl2 and SF6

Molecular mass of Cl2 is 70.906 g/mol, while that of SF6 is 146.06 g/mol

Therefore, the ratio of their rates of diffusion will be;

√(MM of SF6)/√(MM of Cl2) = √ 146.06/√70.906

                                              = 1.4352

                                              = 1.43

Therefore; the two gases required are Cl2 and SF6

there is none because earth is stationary and flat.