To answer the first question, you need to understand Dalton's Law of Partial Pressures. According to Dalton's Law, the total pressure exerted by a mixture of gases is equal to the sum of the partial pressures of each individual gas.
In this case, the total pressure in the container is given by the sum of the pressures of nitrogen (N2), oxygen (O2), and xenon (Xe). So, you need to add the given pressures together: 1.2 atm + 3.2 atm + 0.56 atm = 4.96 atm.
Now let's look at the options provided:
a. 5.0 atm
b. 1.4 atm
c. 2.2 atm
d. 1.0 atm
e. 1.7 atm
Based on the calculations, the total pressure is 4.96 atm. None of the options match exactly, but option a (5.0 atm) is the closest. So, your initial assumption that the correct answer is A is correct.
Moving on to the second question, at Standard Temperature and Pressure (STP), the molar volume of a gas is always 22.4 liters. This is a well-known concept and is represented by Avogadro's Law. According to Avogadro's Law, equal volumes of gases, at the same temperature and pressure, contain an equal number of particles (atoms, molecules, or ions).
Now let's look at the options provided:
a. always 22.4 L
b. varies with the type of gas
c. dependent upon the temperature and pressure of the gas
d. directly proportional to the molar mass of the gas
e. always 6.02 x 10^23 L
Based on the understanding of Avogadro's Law, the correct answer to this question is indeed option a, which states that the molar volume of a gas at STP is always 22.4 L.
In both cases, your initial assumptions were correct. Well done!