Question

In: Chemistry

For questions 2 to 4 d, consider two 2.00 L flasks, one of which contains 0.250...

For questions 2 to 4 d, consider two 2.00 L flasks, one of which contains 0.250 mole of O2

gas at 50.0 deg C and the other of which contains 0.500 mole of H2 gas at 50.0 deg C.

2.      Which sample contains more molecules? Show your calculation. (6 pt)

3.      Which sample has the greater mass? Show your calculation. (6 pt)

4.      a.      In which flask is the ratio of molecular volume (volume occupied by the

                  molecules touching one another in a condensed state) to gaseous sample

                  volume (volume occupied by the entire gaseous sample) greater? (2 pt)

         b.      What is the approximate value of these ratios? Explain. Calculation

                  not needed (4 pt)

         c.      In which sample do the molecules have higher average kinetic energy? Explain.

                  Calculation not needed (4 pt)

         d.      In which flask do the molecules have higher average speed? Explain.

                  Calculation not needed (4 pt)

Solutions

Expert Solution

Two flasks :

First have 0.250 mol O2

Second has 0.500 mol H2

2. Number of molecules of O2 in flask = 0.250 mol x 6.023 x 10^23 = 1.50 x 10^23 molecules

Number of molecules of H2 in flask = 0.500 mol x 6.023 x 10^23 = 3.01 x 10^23 molecules

So, the number of molecules of H2 are greater than O2 in the flask.

3. O2 has higher molar mass so, mass of flask with O2 is heavier than the one with H2 in it.

4. a. Higher moles means greater molecular volume in this case. Here, H2 would be more in gaseous state and hence the ratio of volumes in condensed to gaseous state would be lower. Thus molecular volume for O2 would be higher.

b. Approximate ratios of the molecular volumes of O2/H2 = 2/1

c. Higher velocity molecule would have higher average kinetic energy, so smaller molecule H2 would have greater average kinetic energy as compared to larger and slower molecule O2 in the flask.

d. average speed relation (v),

v = sq.rt.(3RT/molar mass (kg))

with 3RT term constant in both O2 and H2

we can calculate approximate speeds

So,

v(O2) = sq.rt.(1/32 x 10^-3) = 5.59

v(H2) = sq.rt.(1/2 x 10^-3) = 22.36

So, as can be seen, average speed of H2 will be much greater than O2.


Related Solutions

Consider the reaction N2O4 (g) ? 2 NO2 (g). At equilibrium, a 2.00-L reaction vessel contains...
Consider the reaction N2O4 (g) ? 2 NO2 (g). At equilibrium, a 2.00-L reaction vessel contains NO2 at a pressure of 0.269 atm and N2O4 at a pressure of 0.500 atm. The reaction vessel is then compressed to 1.00 L. What will be the pressures of NO2 and N2O4 once equilibrium is re-established?
1. A volume of 18.0 L contains a mixture of 0.250 mole N2 , 0.250 mole...
1. A volume of 18.0 L contains a mixture of 0.250 mole N2 , 0.250 mole O2 , and an unknown quantity of He . The temperature of the mixture is 0 ∘C , and the total pressure is 1.00 atm . How many grams of helium are present in the gas mixture? 2. A gas sample has a unknown pressure with a temperature of 51 ∘C . The same gas has a pressure of 2.96 atm when the temperature...
A 1.00 L solution contains 2.00×10-4 M Cu(NO3)2 and 2.500×10-3 M ethylenediamine (en). The Kf for...
A 1.00 L solution contains 2.00×10-4 M Cu(NO3)2 and 2.500×10-3 M ethylenediamine (en). The Kf for Cu(en)22+ is 1.00×1020. What is the concentration of Cu2+(aq ) in the solution?
A 1.00 L solution contains 2.00 X 10^-4 M Cu(No3)2 and 1.2 x 10^-3 M Ethylenediamine...
A 1.00 L solution contains 2.00 X 10^-4 M Cu(No3)2 and 1.2 x 10^-3 M Ethylenediamine (en). The Kf for Cu(en)2 2+ is 1.0X10^20 What is the concentration of Cu 2+ (aq) in the solution?
2. A jar contains 5 balls, 4 of which are blue and one red. (a) If...
2. A jar contains 5 balls, 4 of which are blue and one red. (a) If you draw balls one at a time and replace them, what is the expected draw at which you will see the red ball? (b) If you draw balls one at a time, but without replacing them, what is the expected time to see the red ball? 3. A jar contains 1 red ball and an unknown number of blue balls. You make 20 draws...
An urn contains 5 balls, two of which are marked $1, two $4, and one $10....
An urn contains 5 balls, two of which are marked $1, two $4, and one $10. A player is to draw two balls randomly and without replacement from the urn. Let X be the sum of the amounts marked on the two balls. Find the expected value of X. Side note: I know Rx={2,5,8,11,14} and P(X=2) = 1/10 ... etc I just need a proper explanation for finding the values of P(X=2), P(X=5), etc. Thanks!
Two identical flasks of the same volume are labeled A and B. Flask A contains NH3(g)...
Two identical flasks of the same volume are labeled A and B. Flask A contains NH3(g) at   50­­oC and flask B contains HCl (g)­ at 50oC. KE=1/2 mv2. a) Which molecule is moving the most rapidly? Explain. b) Give two ways you could increase the pressure in the flask containing the NH3(g) c) Do both molecules have the same kinetic energy? Justify your answer.
A 6.00-L sample of C 2 H 4 (g) at 2.00 atm and 293 K is...
A 6.00-L sample of C 2 H 4 (g) at 2.00 atm and 293 K is burned in 6.00 L of oxygen gas at the same temperature and pressure to form carbon dioxide and liquid water. If the reaction goes to completion, what is the final volume of all gases at 2.00 atm and 293 K?
An unknown gas contains 85.63% carbon and 14.37% hydrogen by mass. if 2.00 L of the...
An unknown gas contains 85.63% carbon and 14.37% hydrogen by mass. if 2.00 L of the gas at 298 K and 0.420 atm and weights 1.926 g A) What is the molar mass of the unknown gas? B) What is the empirical formula of the gas? C) What is the molecular formula of the gas?
The drawing shows a square, each side of which has a length of L = 0.250...
The drawing shows a square, each side of which has a length of L = 0.250 m. Two different positive charges q1 and q2 are fixed at the corners of the square. Find the electric potential energy of a third charge q3 = -3.00 x 10-9 C placed at corner A and then at corner B.
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT