If you mark a box in error, please note the corrected answer under comments at the end of the exam.

Pre-test Summer 2008

01.  What forms of energy does a burning candle release?

A  Electrical and mechanical

B Chemical and electrical

C Light and heat

D Heat and nuclear

02.  A company collects cans for recycling. Some cans are made of aluminum, and some are made of iron. Which of the following is the best way to separate the two types of cans?

A  Heat the iron cans until they melt

B  Use scissors to cut the cans

C  Use a magnet to pick up the iron cans

D  Float the cans in water

03.  Students were studying properties of water. One student placed a cup containing 80 mL of water in a freezer. Another student placed an identical cup containing 40 mL of water in a different freezer.  Which of the following will be the same for both cups of water?

A  The temperature at which the water freezes

B  The mass of the frozen water

C  The time it takes the water to freeze

D  The volume of the frozen water

04.  A teaspoon of clean, dry sand is added to a cup of warm saltwater. What is most likely to happen after the mixture is stirred and then placed on a table for five minutes?

A  The amount of water will increase.

B  The salt will float to the top.

C  The sand will settle to the bottom.

D  The cup will heat up.

05.  A balance is the best tool for measuring which of the following?

A  The texture of soil

B  The length of a stick

C  The mass of a rock

D  The color of a leaf

06.  Which energy transformation occurs when a match is lit?

A  Chemical energy to heat energy

B  Heat energy to potential energy

C  Electrical energy to heat energy

D  Kinetic energy to potential energy

07.  One of the reactions involved in obtaining pure copper (Cu) from copper-containing rock is Cu₂S + O₂ à 2Cu + SO₂.  Which of the following best describes the reaction?

A  Copper atoms are used to produce more copper atoms.

B  Elements are rearranged into new substances.

C  Atoms of other elements are turned into copper atoms.

D  Compounds change phase from liquid to gas

CO₂ + H₂O + sunlight energy à C₆H₁₂O₆ + O₂

08.  Which molecule in the equation above represents food energy made by plants?

A  Carbon dioxide         

B  Water                               

C  Glucose           

D  Oxygen

09.  Which set of equipment would be used to measure the boiling point of a liquid?

A  Balance, thermometer, and stopwatch

B  Test tube, hot plate, and balance

C  Stopwatch, test tube, and microscope

D  Beaker, hot plate, and thermometer

10.  The transfer of carbon that results from burning fossil fuels will most likely affect Earth in the future by —

A  raising the average global temperature

B  reducing evaporation rates of ocean water

C  decreasing the total mass of plant life

D  making air transparent to ultraviolet light

11.  Which of these is an example of a chemical reaction?

A  A pot of water boiling

B  An iron nail rusting

C  Corn being ground

D  Sugar dissolving in tea

12.  You finish an experiment and are left with three empty beakers that held liquids during the experiment. The best lab practice is to —

A  leave the beakers exactly as they are for the next student

B  turn the beakers upside down to drain in the sink

C  wash the beakers and air-dry them on a rack

D  take the beakers directly to a rack to dry

13. Which letter in this model of a boron atom represents a neutron?

A  W                      BX                      

C  Y                       DZ

14.  Diesel fuel is used in the engines of the machines and trucks at the quarry. Which of these is the main energy transformation as the fuel is used by the engines?

A  Electrical energy is converted to heat energy.

B  Heat energy is converted to potential energy.

C  Electrical energy is converted to kinetic energy.

D  Chemical energy is converted to kinetic energy.

15.According to the periodic table, which of the following best represents a carbon atom?

A 

B 

C 

D 

16. What is the volume of the liquid in the graduated cylinder?

A  40.3 mL

B  48.0 mL

C  430 mL

D  43 mL

17.  The table below shows the number of protons in an atom of four different elements. According to the periodic table, which of these elements is a metal?

A  T                       B  Q                      

C  X                       D  Z

18.  The table below shows that the more carbon atoms a compound has, the higher the compound’s boiling point. Based on the data in the table, a reasonable estimate of the boiling point of the next compound, C₇H₁₆, is —

A  70°C                 B  99°C                

C  120°C               D  142°C

 19.  When a 10% hydrochloric acid solution is heated in an open test tube, the test tube should always be pointed —

A  so bubbles are visible

B  at a 180° angle from the flame

C  toward a ventilated area

D  away from nearby people

20.  A cube  contains 20 mL of a solution. The solution has a mass of 40 grams. What is the density of this solution?

A  0.5 g/mL

B  2.0 g/mL

C  60 g/mL

D  800 g/mL

 ___CO (g) +___O₂ (g) à ___CO₂ (g)

21.  What coefficient values will balance the reaction shown above?

A  2, 2, 1                B  1, 1, 1                

C  2, 1, 2                D  1, 2, 2

22.  Rust (Fe₂O₃) forms on an iron (Fe) pipe after prolonged exposure to humid air. What type of change does this illustrate?

A  Mechanical      B  Nuclear           

C  Chemical         D  Physical

23.  Sheets of ice containing mostly pure water can be formed by decreasing the temperature of saltwater. Which of these best describes this change?

A  Chemical change

B  Physical change

C  Nuclear change

D  Atomic change

24.  Students in a chemistry lab measure the time it takes four different 100 mL solutions to pass through a hole in the bottom of a cup.  Which of the following properties of the solutions is most likely being measured?

A  Buoyancy         B  Mass                

C  Viscosity          D Volume

25.  A sample of water from a stream has a greater density than a sample of distilled water.  Which is the best explanation for the difference in density?

A  Streams have kinetic energy.

B  Distilled water has a neutral pH.

C  Streams can contain dissolved salts.

D  Distilled water can contain dissolved gases.

26.  Which of these are composed of two or more different substances that are chemically combined in a definite ratio?

A  Compounds     B  Mixtures         

C  Elements          D Solutions

27.  A recipe calls for 210 grams of sugar to be dissolved in 0.25 liter of water. After the mixture is stirred, some sugar crystals remain in the water. What can be added to the mixture to help dissolve the remaining sugar crystals?

A  Thermal energy

B  2.0 g of baking soda

C  Ice cubes

D  2.0 g of sodium chloride

 28. In the procedure shown above, a calcium chloride solution is mixed with a sodium sulfate solution to create the products shown. Which of the following is illustrated by this activity?

A  The law of conservation of mass

B  The theory of thermal equilibrium

C  The law of conservation of momentum

D  The theory of covalent bonding

 29. What volume should be reported for the solution in this graduated cylinder?

A  64.0 mL

B  56.2 mL           

C  56.0 mL

D  50.6 mL

          Mass of the beaker = 59.02 g

30.  The data above shows how the mass of an undisturbed beaker of alcohol varied during a class period. Which of the following is the best conclusion that can be made about the investigation?

A  The beaker absorbed moisture from the air.

B  A chemical change occurred in the beaker.

C  The beaker experienced a change of state.

D  Some material evaporated from the beaker.

Freezing Rates

31.  The table shows the time it took to freeze water in two different salt solutions with different salt content. According to the table —

A  freezing rates are the same in each trial

B  water with more salt takes longer to freeze

C  water loses heat at a rate of 1°C per minute

D  salt dissolves more quickly in small amounts of water

32.  Crystals were grown on a string in a clean glass jar containing sugar dissolved in hot water. The crystals grew on the string for several weeks. What kind of crystals are they?

A  String               B  Water              

C  Glass              D  Sugar

33. The pans in this balance are at the same height. According to this information, the mass of the rock sample is —

A  170 grams        B  180 grams       

C  200 grams       D  230 grams

34.  When a chocolate bar is heated by the sun, all of the following are likely to be seen EXCEPT —

A  boiling              B  a liquid            

C  melting            D  shape change

35.  In an activity, 20 grams of salt are dissolved in 70 grams of pure water. The water is then heated on a hot plate. When the water evaporates completely, how much salt will be left?

A  0 grams            B  18 grams                   

C  20 grams         D  22 grams

36. In which container will the water evaporate most quickly?

A

B

C

D

37.  Carbon powder and iron filings are both black powders. When mixed together, they look like one black powder. Which of these would be best to use to separate the iron filings from the carbon powder?

A  magnifying glass       B  heat       

C  magnet                      D  water

38.  Matter can undergo changes. When water boils, a —

A  liquid becomes a solid

B  solid becomes a liquid

C  liquid becomes a gas

D  gas becomes a solid

39.  On a warm day water was accidentally spilled onto a metal tabletop. Later in the day, the water was gone. The most likely explanation is that someone wiped the water up or that —

A  germs drank the water

B  the table absorbed the water

C  all the water spilled onto the floor

D  the water evaporated into the air

Atomic Radii (nm)

40.  The table shows the atomic radii of some elements in Periods 1 through 4 of the periodic table. Which inference can be made from this information?

A  Atomic radii decrease from left to right.

B  Atomic radii increase from bottom to top.

C  Atomic radii decrease from right to left.

D  Atomic radii double from top to bottom.

An activity is designed that allows a student to observe the temperature changes in a cup of water.  A piece of metal taken from a beaker of boiling water is placed in a cup containing water at room temperature. A glass alcohol thermometer is used to measure temperature changes.

41.  A safety checklist for this activity should include the presence of a proper fire extinguisher and all the following items except a —

A  fire blanket

B  receptacle for broken glass

C  laboratory apron

D  squeeze bottle

H₂SO₄ + 2NaOH à Na₂SO₄ + 2H₂O

42. Th