Properties of Substances
Which is evidence of a chemical reaction?
A. the light produced by magnesium when burned
B. the evaporation of water from a solution
C. the fizzing of a soft drink
D. the heat from a light bulb
A. the light produced by magnesium when burned
Which statement best describes the change to an ice cube as it melts?
A. The change is physical because the mass remains the same.
B. The change is physical because the substance remains the same.
C. The change is chemical because water has a different pH than ice.
D. The change is chemical because ice has a lower density than water.
B. The change is physical because the substance remains the same.
A hot pack is a product that releases heat when chemicals inside it interact. What is taking place inside an active hot pack?
A. electric current
B. a net loss of mass
C. thermal insulation
D. an exothermic reaction
D. an exothermic reaction
Which statement correctly describes the function of a heat pump in a house?
A. It uses energy to move heat to heat a room.
B. It uses energy to move cold to cool a room.
C. It uses energy to move heat from one place to another to heat or cool a room.
D. It uses energy to move cold from one place to another to heat or cool a room.
C. It uses energy to move heat from one place to another to heat or cool a room.
A construction worker hit a solid steel wall with a sledgehammer, but the wall did not move. Part of the energy exerted by the worker
A. was destroyed by the steel wall.
B. was converted into heat.
C. disappeared into the atmosphere.
D. was stopped by the hard surface.
B. was converted into heat.
An electrical circuit can be used to break down water into hydrogen and oxygen. In this process, electrical energy produces
A. kinetic energy.
B. physical changes.
C. chemical changes.
D. potential energy.
C. chemical changes.
When a mixture of oxygen and hydrogen is ignited in a test tube, the reaction shown occurs.
Hydrogen + Oxygen --> Water + Energy
What happens to the total mass of the contents of the test tube?
A. The total mass increases.
B. The total mass decreases.
C. The total mass remains the same.
D. Part of the mass is changed to heat energy.
C. The total mass remains the same.
A student is organizing a room. She moves a box from the floor to a shelf. She wants to estimate the potential energy the box has on the shelf. What information does the student need?
A. the volume and mass of the box
B. the mass of the shelf and the mass of the box
C. the mass of the box and the height of the shelf
D. the volume of the box and the height of the shelf
C. the mass of the box and the height of the shelf
Why is covering up with a thick, fluffy blanket a good way to stay warm on a cold night?
A. The blanket produces heat that warms your body.
B. The blanket transfers thermal energy from the room to your body.
C. The blanket decreases the transfer of thermal energy from your body to the air.
D. The blanket increases the amount of thermal energy that your body produces.
C. The blanket decreases the transfer of thermal energy from your body to the air.
Coal, oil, and natural gas have high potential energies, which makes them valuable energy resources. In order to benefit from the energy available in these fossil fuels, the potential energy is converted most directly into which type of energy?
A. chemical
B. electrical
C. solar
D. thermal
D. thermal
Ozone is three oxygen atoms bonded together. It can sometimes be smelled in the air after a thunderstorm. The smell is a result of
A. pollution.
B. condensation.
C. a chemical change.
D. a physical change.
C. a chemical change.
How does the concept of conservation of mass apply to chemical reactions?
A. The reactants and products have exactly the same atoms.
B. The reactants and products have exactly the same molecules.
C. The change in the amount of matter is equal to the change in energy.
D. The change in the amount of matter is only a small percentage of the total mass.
A. The reactants and products have exactly the same atoms.
As a satellite falls toward Earth, the gravitational force between the satellite and Earth increases. Which statement best explains why there is an increase in gravitational force?
A. As the satellite gets closer to Earth, the satellite cools.
B. As the satellite approaches Earth, the satellite rotates faster.
C. The mass of the satellite increases as it nears Earth.
D. The distance between Earth and the satellite decreases.
D. The distance between Earth and the satellite decreases.
As water starts to freeze, the molecules of water
A. gain thermal energy.
B. move more freely.
C. increase in size.
D. decrease in speed.
D. decrease in speed.
What tool do you use to measure the average kinetic energy in an object?
Thermometer
Which is an example of a chemical change?
A. heating a block of ice to form liquid water
B. heating a tungsten wire until it glows brightly
C. adding sugar crystals to water to form a clear, colorless liquid
D. passing an electric current through water to form hydrogen and oxygen
D. passing an electric current through water to form hydrogen and oxygen
What happens to a wooden log when it is burned?
A. It is completely destroyed.
B. It is completely changed into heat energy.
C. It changes into other types of matter and energy.
D. It physically changes into the gaseous phase.
C. It changes into other types of matter and energy.
Two identical books are on opposite ends of a table. Which of these would increase the gravitational force exerted between the two books?
A. decrease the distance between the books
B. decrease the mass of the books
C. decrease the mass of the table
D. decrease the temperature in the room
A. decrease the distance between the books
Which statement describes the movement of the particles of a liquid?
A. Particles vibrate in fixed positions.
B. Particles do not move or vibrate.
C. Particles are in constant random motion.
D. Particles move freely throughout the available volume.
C. Particles are in constant random motion.
Put into scientific notation 1,500,000
1.5 x 10^6
When coal burns, the reaction
A. releases heat and is endothermic.
B. releases heat and is exothermic.
C. absorbs heat and is endothermic.
D. absorbs heat and is exothermic.
B. releases heat and is exothermic.
A type of cold pack has two separate sections inside. One section contains a liquid and the other section contains a powder. When the cold pack is squeezed, the section that holds the liquid breaks. When the liquid combines with the powder, the pack becomes very cold. Which is the best explanation for why the temperature of the pack decreases when the liquid and powder combine?
A. A mixture forms.
B. A solution forms.
C. A chemical change occurs.
D. Thermal energy is used.
C. A chemical change occurs.
A metal container on the stove gets hot by
A. conduction of heat energy.
B. convection of heat energy.
C. radiation of heat energy.
D. refraction of heat energy.
A. conduction of heat energy.
A baseball player swings his bat and hits a ball along the ground. After some time, the ball rolls to a stop on the level playing field. What most likely causes the ball to stop moving?
A. a frictional force
B. the size of the bat
C. the mass of the ball
D. a gravitational force
A. a frictional force
________________ created a table that organized different elements by their shared properties and atomic mass.
Dmitri Mendeleev