General Chemistry  

THQ 3 – Review –  General Chemistry

• You have the following reaction: N₂ + H₂ ®NH₃ . (Show the work to get credits)

1. a) What is the balanced equation?

1. What are the molecular shapes of the reactants and the product?

• What is the hybridization of NH₃?

1. How many sigma (s) and pi (p) bonds are there in each reactant and product?
2. Determine the formal charge of each atom in the reactants and the products.
3. Which of the following bonds would be the most polar? Justify.
4. a) C-C b) C-O           c)C-F                         d) C-N
5. What are the intermolecular forces? Define each type. Which one is the strongest?
6. Define and give examples of: covalent bond, network bond, ionic bond, and metallic bond.
7. Calculate the temperature at which the vapor pressure of water is 1200 mm Hg, given that

DHvap is 4.07 x 10⁴ J/mol at 100 ºC. P₁ = 760 mmHg and R = 8.31 J/mol.K. Use Clausius-Clapeyron equation.

6. True or False:
7. a) KNO3, an ionic solid

__________, does not conduct electricity

__________, is soluble in water

__________, can conduct electricity when the solid is melted

7. Determine the concentration of the solution if 75 mL of a 2.4 M solution of sodium chloride is diluted to 500 mL.
8. How many moles of calcium chloride do you need in 256 mL of solution to make a 0.250 M solution?
9. Calculate the mass percent of water in a solution made up of 153 g of NaOH and 275 g of water.
10. Calculate the molality of a solution containing 14.5 g of naphthalene (C₁₀H₈) in 84.3 g benzene (C₆H₆).
11. How many grams of carbon dioxide gas is dissolved in a 1.5 L bottle of carbonated water if the manufacturer uses a pressure of 2.4 atm in the bottling process at 25 °C? (Henry`s Law)
    Given: K_Hof CO₂in water = 3.1 x 10^-2 M/atm at 25 °C.
12. A solution contains 52.0 g of glucose, C₆H₁₂O₆, in 523 g of water. Calculate the vapor pressure of the solution at 25°C. Vapor pressure of pure water at 25°C is 23.76 mm Hg. (Raoult`s Law)
13. Give the definition of colligative properties.
14. An antifreeze solution is prepared containing 30.0 cm³ of ethylene glycol, C₂H₆O₂ (d = 1.12 g/cm³), in 60.0 g of water. k_f = 1.86 ºC/m. Calculate the freezing point of the mixture.
15. Henry`s Law implies that:
16. a) higher pressure favours decreased solubility
17. b) lower pressure favours decrease solubility
18. c) gases should be infinitely soluble in solids

16. Calculate the osmotic pressure at 25°C of a solution prepared by dissolving 65.0 g of sugar, C₁₂H₂₂O₁₁, in enough water to form one liter of solution

17. Estimate the freezing points of 0.30 m aqueous solutions of KNO_3.

Last Updated on April 22, 2019