Chemistry Answers

Calculate the percent by mass of the solution in each of the following aqueous solutions.

a)    5.50 g of NaBr in 78.2 g of solution

b)    31.0 g of KCl in 152g of water

c)    4.5g of toluene in 29g of benzene

1. Calculate the molality of a sulfuric acid solution containing 23.2g of sulfuric acid in 192g of water. The molar mass of sulfuric acid is 98.08 g.
2.  What is the molality of a solution containing 8.82 g of Urea (NH₂)₂CO in 216g of water.
3. A sample of 5.42 g of naphthalene is dissolved in 79.8g of benzene (C₆H₆). Calculate the percent by mass of naphthalene in the solution.
4. Calculate the molality of a 34.6 percent (by mass) aqueous solution of sodium chloride.

Complete the following for aqueous solutions of Aluminum nitrate. Show Complete Solution.

1. Mass of Solute= 2.544g, Molarity= 1.688M, Volume of Solution=____
2. Mass of Solute= _____, Molarity= 0.729M, Volume of Solution= 894mL

How many grams of NaOH are in 3 liters of a 1M solution of the NaOH?

Freon in air conditioning unit has a volume of 0.30L. It is allowed to function in a room, where the pressure is about 628 mm of Hg, assuming that the temperature is in a constant state. Find the final pressure of Freon when its volume is increased to 0.95L.

What will happen to a spray can of paint containing only the propellant at a pressure of 750torr at 30°C if it is thrown into a heap of garbage burning at 165°C?

A 132mL of gas is measured at 38°C. If the pressure remains constant, what will be the volume of the gas at 10°C?

a) How does the rate of the reaction change as you go along the series HF – HCl

– HBr – HI?

b) Briefly explain the trend you have given in part (a).

c) How does the rate of reaction change as you go from ethene to propene to 2-

methylbut-2-ene?

1. Show the structural formulae for the main product of each of the following

addition reactions between various alkenes and a hydrogen halide.

a) Ethene and hydrogen bromide

b) But-2-ene and hydrogen chloride

c) But-1-ene and hydrogen chloride

d) Propene and hydrogen iodide

e) 2-Methylbut-2-ene and hydrogen iodide

f) But-1-ene and hydrogen bromide where everything is pure

g) but-1-ene and hydrogen bromide in the presence of oxygen or

organic peroxides

1. Show the structural formulae for the main product of each of the following

addition reactions between various alkenes and a hydrogen halide.

a) Ethene and hydrogen bromide