THQ 3 – Review – General Chemistry
- You have the following reaction: N2 + H2 ®NH3 . (Show the work to get credits)
- a) What is the balanced equation?
- What are the molecular shapes of the reactants and the product?
- What is the hybridization of NH3?
- How many sigma (s) and pi (p) bonds are there in each reactant and product?
- Determine the formal charge of each atom in the reactants and the products.
- Which of the following bonds would be the most polar? Justify.
- a) C-C b) C-O c)C-F d) C-N
- What are the intermolecular forces? Define each type. Which one is the strongest?
- Define and give examples of: covalent bond, network bond, ionic bond, and metallic bond.
- 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.
- True or False:
- a) KNO3, an ionic solid
__________, does not conduct electricity
__________, is soluble in water
__________, can conduct electricity when the solid is melted
- Determine the concentration of the solution if 75 mL of a 2.4 M solution of sodium chloride is diluted to 500 mL.
- How many moles of calcium chloride do you need in 256 mL of solution to make a 0.250 M solution?
- Calculate the mass percent of water in a solution made up of 153 g of NaOH and 275 g of water.
- Calculate the molality of a solution containing 14.5 g of naphthalene (C10H8) in 84.3 g benzene (C6H6).
- 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: KHof CO2in water = 3.1 x 10-2 M/atm at 25 °C.
- 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)
- Give the definition of colligative properties.
- An antifreeze solution is prepared containing 30.0 cm3 of ethylene glycol, C2H6O2 (d = 1.12 g/cm3), in 60.0 g of water. kf = 1.86 ºC/m. Calculate the freezing point of the mixture.
- Henry`s Law implies that:
- a) higher pressure favours decreased solubility
- b) lower pressure favours decrease solubility
- c) gases should be infinitely soluble in solids
- 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
- Estimate the freezing points of 0.30 m aqueous solutions of KNO3.