Unit 1 Chem(Chapter 1 and 2)
If a mixture is not uniform throughout, it is called
b. heterogeneous.
All of the following are examples of units except
b. mass.
The symbol mm represents
b. millimeter.
All known chemical elements are organized into groups based on similar chemical properties in the
b. periodic chart.
A numerical result is said to have good precision if
b. repeated measurements agree closely.
Which of the following is an example of a homogeneous mixture?
b. salt dissolved in water
The physical state of copper at 25 °C (room temperature) is ________.
b. solid
The relationship between the mass m of a material, its volume V, and its density D is
d. D = m/V.
Which of the following observations is qualitative?
d. Salt crystals formed as the liquid evaporated.
When an egg is fried, what type of process is happening?
d. a chemical change
Which of these metric units is used to measure mass?
g
The vertical columns on the periodic table are called
b. groups.
The SI base unit for length is the
meter
Which of the following is an extensive property of matter?
volume
Which of these is a measure of Earth's gravitational pull on matter?
weight
How many significant digits should be shown in the product of 1.6 cm and 2.4 cm?
2
How many significant figures would the answer to the following calculation have?
3
The number of significant figures in the measured value 0.0320 g is
3
The number of significant figures in the measurement 2010 cm is
3
A temperature of 41 °F is the same as ________°C.
5
Which of the following is a physical change?
b. dry ice subliming
Which of these measurements has been expressed to three significant figures?
a. 0.202 g
The measurement 0.020 L is the same as
a. 2.0 x 10-2 L.
A serving of fish contains 50. g protein and 4.0 g of fat. If the caloric value of protein is 4 kcal/g and fat is 9 kcal/g, how many kcal are in the serving? Report the answer to 2 significant figures.
a. 240 kcal
In the winter, the outdoor temperature is -12 °F. What is the temperature in the Kelvin scale?
a. 249 K
When 64.4 is divided by 2.00, the correct number of significant figures in the result is
a. 3.
Which of these measurements has been expressed to four significant figures?
a. 30.00 mm
The dimensions of a rectangular solid are measured to be 1.27 cm, 1.3 cm, and 2.5 cm. The volume should be recorded as
a. 4.1 cm3.
Three samples of 1.12 g, 1.8 g, and 1.562 g are mixed together. The combined mass of the three samples, expressed to the correct number of significant figures, would be recorded as
a. 4.5 g.
How is the measurement 0.000065 cm written in scientific notation?
a. 6.5 x 10-5 cm
The temperature of liquid nitrogen is -196 °C. What is the corresponding reading on the Kelvin scale?
a. 77 K
Identify the chemical change in the following list.
a. Gold metal is formed from gold chloride in solution.
A compound is
a. a substance, made of two or more atoms that are chemically bonded, that can be broken down into simpler, stable substances.
Which of the following is an intensive property of matter?
a. density
Which of the following is an example of a physical change?
a. grinding coffee beans
Which of the following is an example of a physical change?
a. grinding pepper
The liquid state of matter can be described as
a. having a definite volume but not a definite shape.
If a mixture is uniform in composition, it is said to be
a. homogeneous.
A pure substance is matter that consists of matter with a composition that ________.
a. is fixed in a definite proportion at all times
Which of the following is not a chemical change?
a. melting
When saccharine dissolves in water, this event is an example of a ________.
a. physical change
Which of the following is an example of a heterogeneous mixture?
a. sand mixed with oil
Noble gases are in Group 18, and are best known because they are
a. unreactive.
The unit m3 measures
a. volume.
Which of the following is a chemical change?
a. wood burning in a fireplace
A chemical can be defined as
any substance that has a definite composition.
The phrase "ability to do work" is a definition of ________.
b. energy
The measurement 0.035550 g rounded off to two significant figures would be
b. 0.036 g.
100 milliliters is equivalent to
b. 1 deciliter.
An analytical balance can measure mass to the nearest 0.0001 g. In scientific notation, the accuracy of the balance would be expressed as
b. 1 x 10-4 g.
What is 1.245 633 501 x 108 rounded to four significant figures?
b. 1.246 x 108
A sample of gold has a mass of 96.5 g and a volume of 5.00 cm3. The density of gold is
b. 19.3 g/cm3.
The number of significant figures in the measurement 0.000305 kg is
b. 3.
A cheeseburger from a fast food restaurant contains 19 g of fat, 20. g of carbohydrate, and 28 g of protein. How many kcal of energy does the cheeseburger contain? (The accepted caloric values for foods are 4 kcal/g for carbohydrate, 9 kcal/g for fat, and 4 kcal/g for protein.) Report the answer to 2 significant figures.
b. 360 kcal
When 6.02 x 1023 is multiplied by 9.1 x 10-31, the product is
b. 4.3 x 10-7.
The product of 13 cm and 5.7 cm is correctly reported as
b. 74 cm2.
Identify the chemical change in the following list.
b. A house burns.
Which of these statements about density is true?
b. Density is a physical property.
Which one of the following properties describes a liquid?
b. Its particles are close together and move randomly.
Identify the physical change in the following list.
b. Yarn is knitted into a cape.
A mixture is
b. a blend of any two or more kinds of matter, as long as each maintains its own unique properties.
It is easy to determine whether a substance is a metal if the substance is
b. a good electrical and heat conductor.
A homogeneous mixture is also called
b. a solution.
The quantity of matter per unit volume is
b. density.
Which is the chemical change in the following list?
b. digestion of bread
The two most important properties of all matter are
b. taking up space and having mass.
Which of the following is a physical change?
b. water freezing
Which of these measurements has only nonsignificant zeros?
c. 0.0037 mL
The density of pure diamond is 3.5 g/cm3. What is the volume of a diamond with a mass of 0.25 g?
c. 0.071 cm3
1.06 L of water is equivalent to
c. 1060 mL.
Using a metric ruler with 1 mm divisions, the sides of a rectangular piece of plywood were measured as 3.54 cm and 4.85 cm, which corresponds to an area of 17.1690 cm2. Which of these shows the area expressed correctly?
c. 17.2 cm2.
0.25 g is equivalent to
c. 250 mg.
The average distance between the Earth and the moon is 386 000 km. Expressed in scientific notation, this distance is written as
c. 3.86 ´ 105 km.
On a hot day, the thermometer reads 95 °F. What is the temperature in degrees Celsius?
c. 35 °C
How would 0.00930 m be expressed in scientific notation?
c. 9.30 ´ 10-3 m
Which of the following observations is quantitative?
c. The liquid boils at 100°C.
When you observe the formation of fog on a cool, humid day, what type of event are you observing?
c. a physical change in water
A solid substance is
c. always the same shape regardless of its container.
When a firecracker explodes, giving off light and heat, and breaking the wrapper into many pieces, ________.
c. both a physical and a chemical change are taking place
Which of the following is an example of a heterogeneous mixture?
c. granite
The symbols for units of length in order from largest to smallest are
c. km, m, cm, mm.
The energy stored in the chemical bonds of a molecule is ________.
c. potential energy
In which of the following would the particles move most rapidly?
c. steam at 110 °C
An atom is
c. the smallest unit of matter that maintains its chemical identity.
Compounds are pure substances that by definition consist of ________.
c. two or more elements in combination
0.05 cm is the same as
d. 0.5 mm.
A patient has a temperature of 38.5 °C. What is the temperature in degrees Fahrenheit?
d. 101.3 °F
When 1.92 x 10-6 kg is divided by 6.8 x 102 mL, the answer is:
d. 2.8 x 10-9 kg/mL.
When 5.7 m is divided by 2 s, the quotient is correctly reported as
d. 3 m/s.
The density of aluminum is 2.70 g/cm3. What is the mass of a solid piece of aluminum with a volume of 1.50 cm3?
d. 4.05 g
What is the density of 37.72 g of material whose volume is 6.80 cm3?
d. 5.55 g/cm3
The number of grams equal to 0.5 kg is
d. 500.
A measurement that closely agrees with an accepted value is best described as
d. accurate.
A nonmetal is usually
d. brittle.
Which of the following is not a physical change?
d. burning
Which of the following would NOT be a physical change?
d. burning gasoline in a lawnmower
Which of the following is a chemical change?
d. burning sugar
Which of the following is an example of a chemical change?
d. digesting a hot dog
The SI base units for length and time are
d. meter and second.
Global warming is believed to result from all of the following except ________.
d. movement of the earth closer to the sun
If repeated measurements agree closely but differ widely from the accepted value, these measurements are
d. precise, but not accurate.
These values were recorded as the mass of products when a chemical reaction was carried out three separate times: 8.83 g; 8.84 g; 8.82 g. The mass of products from that reaction is 8.60 g. The values are
d. precise, but not accurate.
The SI base unit for time is the
d. second.
Metalloids are often
d. semiconductors.
The physical state(s) present when a substance is melting is (are) ________.
d. solid + liquid
Which pair of quantities determines the density of a material?
d. volume and mass
The energy of 4.72 kJ is the same as ________ cal.
e. 1130
A potato contains 20 g of carbohydrate. If carbohydrate has a caloric value of 4 kcal/g, how many kcal are obtained from the carbohydrate in the potato?
e. 80 kcal
Identify the physical change in the following list.
e. Silver is melted and formed into a candlestick.
Which of the following is a property of a solid?
e. The particles have fixed positions and are very close together.
When gold is melted and formed in a mold to make a piece of jewelry, what type of change is taking place?
e. a physical change
Compounds can be broken down into their elements by ________.
e. chemical processes
Which of the following quantities is NOT required to calculate the amount of heat energy required to heat water from 25 °C to 55 °C?
e. the heat of vaporization for water
Which of these symbols represents a unit of volume?
mL
A measure of the quantity of matter is
mass
Which of these is a measure of the amount of material?
mass
The horizontal rows on the periodic table are called
periods