Chem Test Review Ch 1-2
The result of (3.8621 × 1.5630) - 5.98 is properly written as
0.06
Select the answer that expresses the result of this calculation with the correct number of significant figures (13.602 * 1.90 * 3.90) / (4.2*1.4097)
13
Acetone, which is used as a solvent and as a reactant in the manufacture of Plexiglas®, boils at 56.1°C. What is the boiling point in degrees Fahrenheit?
133 degrees F
In an average year the American chemical industry produces more than 9.5 million metric tons of sodium carbonate. Over half of this is used in the manufacture of glass while another third is used in the production of detergents and other chemicals. How many pounds of sodium carbonate are produced annually?
2.1 × 10^10 lb
A sample of iron ore, which consists of iron, oxygen, silicon, and carbon, is 33.2% Fe by weight, 24.2% O, 26.3% Si, and 16.3% C. In a 755 kg sample of the ore, how many kg of metals are there?
251 kg
Select the answer with the correct number of decimal places for the following sum: 13.914cm + 243.1cm + 12. 00460cm
269.0 cm
Phosgene, COCl 2, was the first designed war gas. It was used with terrible effects during WWI. What mass percent chlorine is phosgene?
71.69%
Express 96,342 m using 2 significant figures
9.6 * 10^4
The number 6.0448, rounded to 2 decimal places, becomes 6.05.
False
The ripening of fruit, once picked, is an example of physical change
False
Which of the following is a metalloid?
Germanium, Ge, Z = 32
You prepare 1000. mL of tea and transfer it to a 1.00 quart pitcher for storage. Which of the following statements is true?
The pitcher will be completely filled and a small amount of tea will overflow.
The substance, CaSe, is used in materials which are electron emitters. What is its name?
calcium selenide
The substance, CoCl 2, is useful as a humidity indicator because it changes from pale blue to pink as it gains water from moist air. What is its name?
cobalt(II) chloride
When applying the scientific method, it is important to avoid any form of hypothesis
false
What is the name of IF 7?
iodine heptafluoride
The S.I. base unit of mass is
kg
A red glaze on porcelain can be produced by using MnSO 4. What is its name?
manganese(II) sulfate
Water is less dense than ice because
molecules in the gas phase have more space between them than in solids
Water vapor is less dense than ice because
molecules in the gas phase have more space between them than in solids.
The compound, NaH 2PO 4, is present in many baking powders. What is its name?
sodium dihydrogen phosphate
What is the name of Na 2O?
sodium oxide
The compound, P 4S 10, is used in the manufacture of safety matches. What is its name
tetraphosphorus decasulfide
What is the name of P 4Se 3?
tetraphosphorus triselenide
Which of the following is a metal?
thallium, Tl, Z = 81
Rutherford bombarded gold foil with alpha (α) particles and found that a small percentage of the particles were deflected. Which of the following was not accounted for by the model he proposed for the structure of atoms?
the total mass of the atom
When applying the scientific method, a model or theory should be based on experimental data.
true
If the price of gold at the morning fixing in London was $5310 per lb, what would a kilogram of gold have cost in £ (pounds)? (Assume an exchange rate of $1.00 = £0.545)
£6370
A flask has a mass of 78.23 g when empty and 593.63 g when filled with water. When the same flask is filled with concentrated sulfuric acid, H 2SO 4, its mass is 1026.57 g. What is the density of concentrated sulfuric acid? (Assume water has a density of 1.00 g/cm 3 at the temperature of the measurement.)
1.840 g/cm3
Which of the following represents the largest volume?
100 mL
Select the answer that expresses the result of this calculation with the correct number of significant figures and with correct units 16.18cm * 9.6114 / 1.4783
105.2
The S.I. prefix mega- (M) means
10^6
Acetic acid boils at 244.2°F. What is its boiling point in degrees Celsius?
117.9 degrees Celsius
Magnetite is a natural iron ore; in some deposits, it has a natural magnetism and it was used in the first compasses by Chinese and by Viking sailors. If Magnetite is Fe 3O 4, what percentage by weight of oxygen is it?
27.6%
A dose of medication was prescribed to be 35 microliters. Which of the following expresses that volume in centiliters?
3.5 * 10^-3
The average distance between the Earth and the Moon is 240,000 miles. Express this distance in kilometers
3.9 × l0^5 km
A large pizza has a diameter of 15 inches. Express this diameter in centimeters
38 cm
Determine the molecular mass of iron (III) bromide hexahydrate, a substance used as a catalyst in organic reactions.
403.65 amu
The appropriate number of significant figures in the result of 15.234 × 15.208 is
5
Kaolinite, a clay mineral with the formula Al 4Si 4O 10(OH) 8, is used as a filler in slick-paper for magazines and as a raw material for ceramics. Analysis shows that 14.35 g of kaolinite contains 8.009 g of oxygen. Calculate the mass percent of oxygen in kaolinite.
55.81 mass %
"Vinyl" plastic, also called PVC, is a polymer made from vinyl chloride, C 2H 3Cl. What is the percent composition of the chlorine in vinyl chloride?
56.72%
Which measurement is expressed to 4 significant figures?
62.40 g
Which one of the following statements about atoms and subatomic particles is correct?
A neutral atom contains equal numbers of protons and electrons.
Barium sulfate is used in manufacturing photographic paper. What is its formula?
BaSO4
As chief chemist at Superior Analytical Products (SAP) you must design an experiment to determine the density of an unknown liquid to three (3) significant figures. The density is of the order of 1 g/cm 3. You have approximately 7 mL of the liquid and only graduated cylinders and balances are available for your use. Which of the following combinations of equipment will allow you to meet but not exceed your goal?
Graduated cylinder with ±0.01 mL uncertainty; balance with ±0.01 g uncertainty
Which of the following is an extensive property of oxygen?
Mass
Which of the following compounds is ionic?
MgCl2
Sodium peroxide is an oxidizer used to bleach animal and vegetable fibers. What is its formula?
Na2O2
Which one of the following formulas of ionic compounds is the LEAST likely to be correct?
NaSO4
Which one of the following formulas of ionic compounds is the least likely to be correct?
NaSO4
Which one of the following combinations of names and formulas of ions is incorrect?
O2- oxide
Which of the following compounds is covalent?
PCl3
Which one of the following combinations of names and formulas of ions is incorrect?
S2- sulfate
Rutherford bombarded gold foil with alpha (α) particles and found that a small percentage of the particles were deflected. Which of the following was not accounted for by the model he proposed for the structure of atoms?
The total mass of the atom
The potential energy of a car moving on a level road does not depend on its speed.
True
When a wooden match burns in air, chemical potential energy is converted to kinetic energy.
True
What is the name of BBr 3?
boron tribromide