Respuesta :
The combination of gases that will produce a solid closest to the center of the tube would be HCl and CHNH. Thus, A would be the right option.
According to the diffusion law, the rate of diffusion of gases is inversely proportional to the square root of their molar masses.
Following this law, a combination of gases that will diffuse from the opposing ends of the tube to form a white solid around the middle of the tube would be those whose molar masses are close to one another.
- Molar mass of HCl is 36.5, CHNH is 28
- HCl is 36.5, NH3 is 17
- HBr is 80.9, CHNH is 28
- HBr is 80.9, NH is 15
Thus, one can see that the combination of gases with the closest molar mass is HCl and CHNH.
More on diffusion rate of gases can be found here: https://brainly.com/question/2967915