Answer:- Mole ratio of D to A is 4:3.
Explanations:- Mole ratio for a chemical reaction is the ratio of the coefficients.
The given generic chemical reaction is:

The numbers written in front of each chemical species in the chemical reaction are their moles. For the given generic chemical reaction the coefficient of A is 3 and that of B is 1. So, the mole ratio of A to B is 3:1.
Similarly if we want to write the mole ratio of C to D then it is 1:4.
We are asked to write the mole ratio of D to A. So, like the other ratios, the mole ratio of D to A is 4:3 as the coefficient of D is 4 and A is 3.
Answer: Insufficient amount of work provided.
Explanation:
Answer:
Mean Partial pressure of Nitrogen in Mars' atmosphere = 15.86 Pa
Explanation:
According to Dalton's law of Partial Pressure, the total pressure exerted by a mixture of ideal gases (that do not react together) is the sum of the partial pressures of the individual gases that make up the mixture. It goes further to explain that the partial pressure of a gas in a mixture of gases is equal to its mole fraction of that gas multipled by the total pressure exerted by the mixture of gases.
Total Pressure exerted by the mixture of gases in the atmosphere on Mars = Mean atmospheric pressure on Mars = 610 Pa
Partial pressure of Nitrogen = (mole fraction or mole percentage of Nitrogen in the atmosphere) × (total pressure exerted by all the gases in the atmosphere)
Mole percentage of Nitrogen in the atmosphere of Mars = 2.6%
Partial pressure of Nitrogen = 2.6% × 610 = 15.86 Pa
Mean Partial pressure of Nitrogen in Mars' atmosphere = 15.86 Pa
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