Are these correct?
1. A sample of gases contains three gases at the following pressures: 1.2 atm N2, 3.2 atm O2, and 0.56 atm Xe. What is the total pressure in the container?
a. 5.0atm
b. 1.4atm
c. 2.2atm
d. 1.0atm
e. 1.7atm
I am pretty sure it is A. Is that correct?
2. The molar volume of a gas at STP
a. is always 22.4L
b.varies with the type of gas
c. is dependent upon the temperature and pressure of the gas
d. is directly proportional to the molar mass of the gas
e. is always 6.02 x 1023 L
I think this one is A as well.
Thank you for your help!
Those look ok to me.
On 1, remember that Dalton's Law of Partial Pressure says that the total pressure is the sum of all of the partial pressures; therefore, 3.2 + 1.2 + 0.56 = 4.96 atm. Then significant figures comes into play. When adding, the answer may contain only to the tenths place; thus, 4.96 rounds to 5.0 atm.
Thank you Dr Bob!!!!
the valve between a 3.00-L tank containing O2(g) at 6.00 atm. and a 5.00-L containing N2(g) at 1.20 atm. is opened. Calcualte the ratio of partial pressures (O2:N2) in the container?
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!