Principles of Chemistry 1211L
Procedure:
Useful formula Q = m x ∆T x C
· The Periodic Table of Elements is provided for your use. Do not remove from the test bank.
· Do not write your answer on this test.
· Some problems are easier than others. Some advice: save the more difficult problems for the end.
· GOOD LUCK!
1. An experiment calls for 50.0 mL of bromine (d = 3.12 g/mL). Since an accurate balance is available, it is decided to measure the d by mass. How many grams should be measured out?
2. What is the percent yield of the following reaction if 60 grams of CaCO3 is heated to give 15 grams of CaO?
CaCO3→CaO + CO2
3. What is the actual yield of calcium carbonate CaCO3 given in the following data
Mass of crucible = 18.20 g
Mass of crucible + CaCO3 (before heating) = 20.11g
Mass of crucible + CaCO3 (after heating) = 19.202g
4. A mixture of different coloured inks can be separated using…
a) chromatography
b) distillation
c) evaporation
d) filtration
5. What is the volume of a 2.50 gram block of metal whose density is 6.72 grams per cubic centimeter?
6. A cube of 1.2 inches on the side has a mass of 36 grams. What is the density in g/cm3?
(a) 21
(b) 2.2
(c) 30.
(d) 1.3
(e) 14
7. If 100 g water is heated from 20 °C to 50 °C, what is the
heat q gained by the water?
8.In the lab we had one unknown compound. We used thin layer chromatography method for it. The distance travelled by the solvent was 50 mm from the origin to the solvent front. One of the components of the sample travelled 20 mm distance from the origin. What is the Rf of the component?9. The density of a substance is 1.63 grams per milliliter. What is the mass of 0.25 liters of the substance in grams?
10. Calculate the amount of heat in joules needed to increase the temperature of 250 g of water from 30oC to 55oC.
11. A student weighs distilled water in graduate cylinder. The cylinder and water weighs 150 g. The volume of the liquid was determined to be 65mL. What is the weight of the distilled water sample?
12. Which lab is related to Law of thermodynamics?
a. chromatography c. gravimetric analysis
b specific heat d. density
