Chem Pre/Post Test

Which liquid limited the amount of gas produced?

• Liquid A

• Liquid B

• Neither liquid

• Both liquids

What happened to the liquid in the thermometer system?

• The volume of the liquid increased.

• The mass of the liquid increased.

• The kinetic energy of the particles increased.

• The number of particles increased.

• The space between the particles increased.

Did a chemical reaction happen inside the thermometer?

• Yes, because the liquid inside the thermometer takes up more space.

• Yes, because the liquid inside the thermometer became a new substance.

• No, because the liquid inside the thermometer is the same substance.

• No, because the liquid inside the thermometer expanded.

What happens to water particles when they are heated?

• The speed of the water particles increases.

• The size of the water particles increases.

• The number of water particles increases.

• The space between the water particles increases.

• The number of collisions between water particles increases.

If this reaction occurs in a closed system, what happens to the mass of the matter?

• The mass decreases because the number of molecules decreased.

• The mass stays the same because matter is conserved in reactions.

• The mass increased because the new molecules are denser.

• The mass stays the same because the system was closed.

Consider what happens to sugar particles when sugar is melted or dissolved in water.

• Sugar melts when the bonds between sugar particles break.

• Sugar melts when the kinetic energy of the sugar particles increases enough for them to move past one another.

• Sugar dissolves when particles get soft enough to turn into liquid.

• Sugar dissolves when liquid particles break sugar particles apart from one another.

• When sugar dissolves, the sugar particles turn into water particles.

A cup of water is surrounded by air at room temperature. Describe the energy transfer between the water and the air if the system is at equilibrium.

• Energy transfers from the air to the water.

• Energy transfers from the water to the air.

• Energy transfers back and forth between the air and water.

• No energy is transferring between the air and water.

Which of the following is evidence that a chemical reaction occurred?

• The products have the same number of elements as the reactants.

• The products include different substances than the reactants.

• The products have the same atoms as the reactants.

• The reactants and products have the same number of molecules.

Which of the following is evidence that mass is conserved during the reaction?

• The products have the same number of elements as the reactants.

• The products include different substances than the reactants.

• The products have the same atoms as the reactants.

• The reactants and products have the same number of molecules.

If you remove all the particles from a wooden table, what remains?

• Sawdust

• Nothing

• A table that has less mass.

• A table that looks the same but weighs less.