CBM 9 Review

The motion of atoms is affected by temperature. The pictures show water at three different temperatures. Place the pictures in order of increasing motion of water atoms using the picture numbers.

• 1, 3, 2

• 2, 1, 3

• 3, 2, 1

• 2, 3, 1

A student is examining three diagrams that show particle arrangements in a solid, liquid, and gas. Which sequence/order represents the decreasing kinetic energy of the particles?

• R, Q, S

• Q, S, R

• S, R, Q

• Q, R, S

Anita heats a beaker containing water. As the temperature of the water increases, which change to the water molecules occurs?

• The molecules move at a faster rate.

• The molecules become more massive.

• The molecules expand and become wider.

• The molecules separate into atoms of hydrogen and oxygen.

How many atoms of oxygen are used in the reaction?

• A. 2

• B. 3

• C. 4

• D. 8

A chemical reaction separates water into hydrogen gas and oxygen gas. Which of the following statements is true about the mass of the water and the combined mass of the two gases?

• The mass of the water is greater than the combined mass of the two gases.

• The combined mass of the two gases is much greater than the mass of the water.

• The combined mass of the two gases is the same as the mass of the water.

• The mass of the water is the same as double the combined mass of the two gases.

Which of the following is a correctly written chemical equation that demonstrates the conservation of mass?

• Mg + HCl → H₂ + MgCl₂

• H₂O + CO₂ → H₂CO₃

• KClO₃ → KCl + O₂

• H₂ + O₂ → H₂O

Which describes what is felt and observed in a system when a chemical reaction releases energy?

• It feels cold, and a decrease in temperature is observed.

• It feels warm, and a decrease in temperature is observed.

• It feels cold, and an increase in temperature is observed.

• It feels warm, and an increase in temperature is observed.

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 why the temperature of the pack decreases when the liquid and powder combine?

• A mixture forms.

• A solution forms.

• A chemical change occurs.

• Thermal energy is used.

A hot pack is a product that releases heat when chemicals inside of it interact. What is taking place inside an active hot pack?

• electric current

• a net loss of mass

• thermal insulation

• an exothermic reaction

A region experiences frequent earthquakes that result in property damage. Engineers are designing a building for the region that can better withstand the effects of earthquakes. Which is an essential feature that the engineers should include in their building design?

• The building should be large to stop earthquake waves when they approach.

• The building should be tall to withstand ground shaking for a long period of time.

• The building should be flexible to move when the ground shakes to absorb energy.

• The building should be built with a deep foundation to help redirect earthquake waves.