Chem120 Week 4 Quiz 2020

Question 1:        (TCO 6) A sample of helium gas occupies 520 mL at 79 mmHg. For a gas sample at constant temperature, determine the volume of helium at 45 mmHg.

Question 2.                     (TCO 6) A gas at a temperature of 65 degrees C occupies a volume of 225 mL. Assuming constant pressure, determine the volume at 150 degrees C.

Question 3.                     (TCO 6) For a gas at standard temperature and pressure with a density of 3.5 g/L, determine its molar mass.

Question 4.                     (TCO 6) Calculate the volume, in liters, of a 1.5 mol H2S(g) at 50 degrees C and 2 atm.

Question 5.                     (TCO 8) According to the Bronsted-Lowry definition, which chemical in the following reaction is the base?   H3PO4

+ H2O -> H3O+ + H2PO4-

                                       H2O

                                         H3O+

                                         H3PO4

                                         H2PO4-

                                         none of the above

Question 6.        (TCO 8) According to the Bronsted-Lowry definition, which chemical in the following reaction is the base?   H3PO4

+ NH3 -> NH4+ + H2PO4-

                                        NH3

                                         NH4+

                                         H2PO4-

                                         H3PO4

                                         none of the above

Question 7.                     (TCO 8) What is reduced in the following reaction?   2 Bi + 3 Mg2+    à  2 Bi3+ + 3 Mg

                                         Mg

                                         Bi

                                         Mg2+

                                         Bi3+

                                         none of the above

 Question 8.       (TCO 8) What is reduced in the following reaction?   Fe2O3 + 3 H2 -> 2 Fe + 3 H2O

                                        Fe2O3

                                         H2O

                                         Fe

                                         H2

                                         none of the above

Question 9.        (TCO 8) What is the pH of a solution with a [H3O+] of 1 x 10-8 M?

                                         -5.0

                                         8

                                         6

                                         5.0

                                         none of the above

Question 10.      (TCO 8) What is the pH of a solution with a [H3O+] of 1 x 10-5 M?

                                         -5.0

                                         10.0

                                         -10.0

                                         5.0

                                         none of the above