Question

2. A piece of sodium metal reacts completely with water as follows:

2Na(s) + 2H₂O(l) à 2NaOH(aq) + H₂(g).

The hydrogen gas generated is collected over water at 25.0^oC. The volume of the gas is 252mL measured at 1.00atm. Calculate the number of grams of sodium used in the reaction. (Vapor pressure of water at 25^oC = 0.0313atm).

a. 0.23g

b.0.25g

c. 0.474g

d. 0.459g

3. Write the ground state electron configuration for Iron.

a. [Kr]5s²4d¹⁰5p⁵

^b. [Rn]7s¹

^c. 1s²2s²2p⁵

^d. 1s²2s²2p⁶3s²3p⁶4s²3d⁶

^4. Draw the Lewis structure and predict the geometry for XeF₄.

a. Tetrahedral

b. Square Planar

c. Trigonal Bipyramidal

d. Octohedral

5.Draw the Lewis structure and predict the geometry for SF₄.

a. Trigonal Pyramidal

b. Trigonal Bipyramidal

c. Seesaw

d. Linear

6. For the redox reaction below give the half reaction for Oxygen.

4Fe + 3O₂ à 2Fe₂O₃

a. 3O₂⁰ à 2O₃^-2 + 12e-

b. O₂⁰ à O₃^-2 + 6e-

c. 3O₂⁰ + 12e- à 2O₃^-2

^d. O₂⁰ + 6e- à O₃^-2

^7. Calculate the wavelength (nm) of the emitted photon when an electron drops from the n=5 to the n=2 level in a hydrogen atom.

a. 362nm

b. 486nm

c. 434nm

d. 225nm

8. Draw the Lewis structure and predict the geometry for PbCl₂.

a. Trigonal Pyramidal

b. Bent

c. Trigonal Planar

d. Tetrahedral

9. The work done to compress a gas is 88J. As a result, 20J of heat is given off to the surroundings. Calculate the change in energy of the gas.

a. 108J

b. -68J

c. +68J

d. 48J

10.Specify the group of the periodic table in which the following element is found: [Ne]3s²3p¹.

a. 1A

b. Transition Metal

c. 2A

d. 3A

11. 456.7µm = ________m

a. 4.567 x 10^-3

^b. 4.567 x 10^-4

^c. 456.7 x 10^-3

d. 456.7 x 10^-4

^12. Which of the following compounds is ionic?

a. HCI

b. MnO

c. NO₂

_d. N₂H₄

_13. A six foot person weighs 254lbs. Express this person’s weight in kilograms. (1lb = 453.6g).

a. .56kg

b. 97.52kg

c. 115.21kg

d. 1.79kg

14. A sample of propane, a component of LP gas, has a volume of 35.3L at 315K and 922torr. What is its volume at STP?

a. 25.2L

b. 37.1L

c. 30.6L

d. 33.6L

15. How many grams of KOH are present in 47.0mL of a 5.50 M solution?

a. 4.61g

b. 14.50g

c. 1450g

d. 217.02g

16. Sulfur dioxide reacts with chlorine to produce thionyl chloride (used as a drying agent for inorganic halides) and dichlorine oxide (used as a bleach for wood, pulp and textiles).

            SO₂(g) + 2Cl₂(g) à SOCl₂(g) + Cl₂O(g)

If 0.400mol of Cl₂ react with excess SO₂, how many moles of Cl₂O are formed?

a. 0.80mol

b. 0.40mol

c. 0.10mol

d. 0.20mol

17. A sheet of gold weighing 25.0g and at a temperature of 20.0^oC is placed flat on a sheet of iron weighing 20.0g and at a temperature of 60.0^oC. What is the final temperature of the combined metals? Assume that no heat is lost to the surroundings. (Specific heat for gold is 0.129 J/g ^oC and specific heat for iron is 0.444 J/g ^oC)

a. 50.83C

b. 49.39C

c. 66.7C

d. 25.42C

18. A 7.00kg piece of copper metal is heated from 18.4^oC to 357.3^oC. Calculate the heat absorbed (in kJ) by the metal. (Specific heat for copper is 0.385 J/g ^oC)

a. 1889kj

b. 913335kj

c. 727.51kj

d. 913.34kj

19. Draw the Lewis structure and predict the geometry for IF₄⁺¹.

a. Octahedral

b. Square Pyramidal

c. Seesaw

d. Trigonal Bipyramidal

20. A photon has a wavelength of 428nm. Calculate the energy of the photon in joules.

a. 1.38 x 10^-39J

b. 4.65 x 10^-38J

c. 4.65 x 10^-19J

d. 3.19 x 10^-19J

21. The relative abundances of ³²₁₆S, ³³₁₆S, and ³⁴₁₆S are 95.0%, 0.80% and 4.2% respectively. Calculate the average atomic mass of sulfur.

a. 34.47amu

b. 3209.20amu

c. 58.19amu

d. 32.09amu