Science Quiz

Saheed chews his food to break it down into smaller pieces. The saliva released by glands in his mouth breaks the carbohydrates he ate down into simpler substances. What changes does the food undergo in Saheed’s mouth?

• Food undergoes a physical change when it is chewed and a chemical change when saliva breaks it down into simpler substances.

• Food undergoes a chemical change when it is chewed and a physical change when saliva breaks it down into simpler substances.

• Food undergoes a physical change when it is chewed and another physical change when saliva breaks it down into simpler substances.

• Food undergoes a chemical change when it is chewed and another chemical change when saliva breaks it down into simpler substances.

Choose the words that correctly complete the paragraph. Each word will be used once. The simplest type of substance is a(n) ______ element ______ , and the basic unit of this substance is a(n) ______ atom ______ . Different elements can combine chemically to form a(n) ______ compound ______ . The basic unit of these substances, called a(n) ______ molecule ______ , is made of two or more atoms. When different substances combine only physically, a(n) ______ mixture ______ forms.

During a lab, Michael was given a sample of a metal to identify. He determined that its mass was 143 g and its volume was 12.6 cubic cm. Use this data and the information in the table to identify the metal.

• gold

• iron

• lead

• silver

Mr. Marcum conducted an experiment to study a sample and its properties. He moved the sample from one container to another. The sample kept the same volume, but its shape changed. From the behavior of the sample, Mr. Marcum knows that the particles that make up the sample touch each other but are free to slide by each other. What is the state of this sample?

• gas

• liquid

• plasma

• solid

Stacy lives in Nebraska, where the winters can be well below freezing point. In the summers, the weather can be quite hot and humid. Suppose Stacy lives near a pond. Which choice shows the changes that most likely occur to the water in the pond from February to July?

• freezing → melting → evaporation

• condensation → freezing → melting

• melting → evaporation → freezing

• melting → evaporation → condensation

Cordell bought new tires for his bicycle. As he rode his bike on the hot street, the temperature of the air in the tires increased. If the volume of the air stayed the same, what happened to the pressure inside the tires?

• It decreased.

• It increased.

• It stayed the same.

• It was inversely proportional to the temperature.

Lydia conducts an experiment to compare the properties of water and vegetable oil. She observes that oil pours more slowly than water. She also observes that more water drops than oil drops can be balanced on the surface of a penny. Which claim is supported by this evidence?

• Water has a higher density than vegetable oil.

• Vegetable oil has a higher viscosity and a higher surface tension than water.

• Water has a lower viscosity, but a higher surface tension, than vegetable oil.

• Water and oil are equal in density, but oil has a higher viscosity.

Javier is the pitcher for his baseball team, the Wildcats. He realized early on during pitching practice that his windup and throw relied on science as well as on his skill. Which of the following best describes a baseball if it changes its position relative to another object, such as a bat?

• It needs more energy.

• It is doing work.

• It is in motion.

• It is making a force.

There are several forms of energy: electromagnetic, radiation, mechanical, electrical, thermal, chemical, and nuclear. Which forms of energy show both potential and kinetic energy?

• electromagnetic, mechanical, thermal

• nuclear, electrical, electromagnetic

• nuclear, thermal, electrical

• mechanical, thermal, electrical

Which statement best describes a transfer of heat?

• An ice cube melts in your mouth, making your tongue cold.

• Rafael feels hot after a hard run around the school property.

• Julie pours iced tea into an insulated travel mug to keep it cold for a few hours.

• Two kittens snuggle together in a box to stay warm.