Science Midterm Review

A certain gas expands to fill a 3 L container. Its mass is measured to be 0.6 kg. What is its density? (Round your answer to the nearest hundredth)

.2 L/kg

A metal ball has a mass of 2kg and a volume of 6 m . What is its density? (Round your answer to the nearest hundredth)

.33 kg/m

Corey notices that ice cream begins to melt when left out at room temperature. What is Corey observing?

physical change

Lauren makes an art piece using the densities of various liquids to create layers of colors. She first determines the density of each liquid. Then she pours them into a glass container and watches them separate into layers, and the density is calculated by g/ml. Dish soap: 1.03, honey: 1.36, corn syrup: 1.33, corn oil: 0.91, water: 1 1. What information did she need to find the density of each liquid? 2. How did she calculate density? 3. Which liquid sinks to the very bottom, and which floats at the very top?

1. She needed the mass and volume of the liquids to find the density. 2. She calculated density by using the formula mass divided by volume. 3. Honey sinks to the bottom and corn oil floats to the top.

Bela made scrambled eggs while camping. She placed the eggs in a pan on the grill, then turned on the flame to apply heat to the pan and to the eggs. By applying heat, Bela increased the thermal energy of the eggs. She could measure how much the temperature increased with a thermometer.

1. Thermal energy 2. Temperature

Calculate the density of sulfuric acid if 35.4 mL of the acid weighs 65.14 g (Round your answer to the nearest hundredth)

1.84 ml/g

The density of aluminum is 2.7 g/cm . What is the volume of a piece of aluminum if its mass is 8.1 grams?

3cm^3

Have you ever noticed that some paints, glues, and nail polish remover have a peculiar smell? What you smell might be acetone. Acetone is a liquid at room temperature. Examine the graph showing what happens when liquid acetone becomes a gas.

30 minutes

Kenneth warmed up a 100-mL sample of air in an expandable container. He displayed the results in the following graph. The results formed a straight line, so he extended the line the full length of the graph. At what temperature did the gas have a volume of 110 mL?

300 K

A rectangular solid has a height of 6 cm, a width of 10 cm, and a length of 5 cm. What is the volume of this solid?

300 cm cubed

The table below shows the density of four liquids in g/ml. A: 0.89, B: 1.64, C: 0.83, D: 0.77 Based on this information, what can you infer about these liquids?

5 mL of liquid B has the same density as 10 mL of liquid B.

Jonah and Rachel volunteer at the recycling center sorting and organizing recyclable objects. Jonah is sorting aluminum cans and crushing the cans to fit more in the bag. Rachel is sorting metal and steel objects into appropriate bins. Rachel notices that many objects have rusted. Rusting is a chemical change that some metal and steel objects undergo when they are exposed to oxygen. Which option best describes a chemical change?

A change in matter that produces one or more new substances

A physical change does not involve a change in the substance's chemical identity. Which of these statements describes a physical change?

Aluminum cans get crushed before recycling

Which process is an example of a chemical change?

An iron nail rusting

Gigi is preparing to cook a family dinner, and she begins by gathering ingredients for the main course and dessert. She realizes that most ingredients go through both physical and chemical changes as they cook. One of the ingredients for her main course undergoes physical changes. Which of the following is a physical change?

Boiling water

Sonja and Jeremy performed several experiments to show how changes in temperature affected the volume of an inflated balloon. They made sure the pressure stayed the same. They also showed the effects of pressure on volume if temperature stayed the same. They organized their information in this table. A: increases, stays the same, increases; B: decreases, stays the same, decreases; C: increases, decreases, stays the same; D: decreases, increases, stays the same. Which experiments provide evidence for Boyle's law?

C and D

Min was writing about changes in the state of matter for a research paper. Which of these changes might she include as examples of sublimation? Choose the two statements that apply.

Clothing is hung outside on a day when the temperature is below the freezing point of water. The clothes dry, even though they freeze first. Dry ice changes directly to carbon dioxide gas.

Use the graph to determine the freezing point of the element. Which of these elements is the "mystery element"? The freezing point of each element is listed by its name.

Cobalt (1495°C)

People who have certain lung diseases, such as emphysema or lung cancer, often have to use oxygen from tanks. A large volume of oxygen can be put into a small tank because oxygen is a gas, and gases can be_______________.

Compressed

Chase and Bernie were ice-fishing at a frozen pond where the temperature was -4⁰C. As the boys sat on the ice, the thermal energy of the ice decreased , and some of the ice melted . As it sat in the cold air, the thermal energy of the water on the glove decreased , and the water on the glove froze .

Decreased, melted, increased, froze

Which statement best identifies which of these models represents a gas? Model A is tightly packed, and Model B is spaced out and far apart.

Diagram B is a gas, because its particles move more quickly and are farther apart.

Annie learns that the compound sulfuric acid is called the universal chemical. The acid is used in everything from gasoline to paper. Annie uses beads in three different colors to model sulfuric acid. Based on the model, what is the chemical formula of sulfuric acid?

H2SO4

For dessert, Kasey prepares to bake a delicious apple pie. During one of the steps, she notices an example of a chemical change. Which one is it?

Heating sugar to make Carmel

Ruth's birthday celebration included several party balloons that were filled with helium. As afternoon sunlight filled the room over time, the room became warmer. As the temperature in the room increased, the volume of the gas in the balloons increased , because gas temperature and volume are directly proportional .

Increased, directly proportional

Which claim is true of all matter?

It has mass

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 in g/cubic cm and the information in the table to identify the metal. Gold: 19.3, iron: 7.8, lead: 11.3, silver: 10.5

Lead

Lainey is a forensic scientist. She has been asked to identify a chemical compound that was found at the scene of a crime. Which of these pairs of properties would be most helpful in identifying the unknown compound?

Melting point, reactivity with water

Elements can be described by various properties, and identified by their boiling and melting points. For example, gold melts at 1,064ºC and boils at 2,856ºC. Does boiling point depend on the mass present?

No; physical properties stay the same regardless of mass.

Liz is exploring the different kinds of changes that can happen to substances. She knows that changes can alter the looks or shape of a substance. Cutting, melting, bending, or crushing are examples of what kind ofchange?

Physical

Matter has two basic properties: physical properties and chemical properties. Which of these statements best describes physical properties?

Physical properties can be observed without changing the identity of a substance.

A scout on a hike becomes lost. He does not have a compass, but he does have a small needle, a magnet, and some water. He magnetizes the needle and then gently places it on the surface of the water, where it points to the north. What property of the water makes it possible for the needle to lie on the surface of the water?

Surface tension

Have you ever noticed that some paints, glues, and nail polish remover have a peculiar smell? What you smell might be acetone. Acetone is a liquid at room temperature. Examine the graph showing what happens when liquid acetone becomes a gas. Describe the behavior of the acetone particles during each phase represented by the diagonal and horizontal portions of the graph.

The acetone is a liquid when it is on the first diagonal line. It remains a liquid up to 55°C and it takes 20 minutes for it to start boiling; as the time increases the temperature increases. The horizontal line shows where the liquid acetone is boiling so that it will become a gas. While the acetone is boiling, the temperature stays the same and it takes ten minutes to boil. On the last diagonal line, it shows that the acetone has become a gas. It became a gas over 55°C. As the time increases, the temperature of the gas increases.

Cameron finds the total mass of a sample of baking soda, a balloon, and a glass container with vinegar in it. She adds the baking soda to the vinegar and immediately places the balloon over the mouth of the container. After the reaction is complete, she again finds the total mass of the system. Which claim is true about this investigation?

The mass does not change because chemical changes observe the law of conservation of mass.

Which of these is a chemical property of a sheet of paper?

The paper can be burned.

Nakeem and his team were playing basketball in the gym, and all the basketballs were firm and bounced well. When the team went outside, the same basketballs seemed a bit flat and would not bounce well. Which statement provides the best explanation for what happened to the basketballs?

The temperature outside was colder than the temperature in the gym, so the pressure of the air in the balls decreased.

Jane increases the temperature of a gas in an expandable container. If she keeps the pressure constant, what will happen to the volume of the gas?

The volume will increase

Chelsea went ice-skating. The ice, her skates, the Zamboni, and the rink building itself were all examples of solids she encountered. She developed a model of the particles in the ice. Which of these statements about the particles present in her model of a solid are true? Choose the three statements that apply.

They vibrate in place, they are packed very closely together, and they cause the solid to have definite volume and definite shape.

Trenton wants to study the chemical properties of iron. Which would provide the evidence he needs to do this?

Trenton could observe the sample's reactivity with moist air.

Darvon observed that a rain puddle he saw on his driveway was gone in a couple of hours. What terms apply to what happened to the water in the puddle?

Vaporization and evaporation

Motor oil has different ratings depending on how readily it flows. This property depends on how much attraction is present between its particles. Which property of a liquid does this illustrate?

Viscosity

The planet Venus is surrounded by a thick layer of gases. In fact, the atmospheric pressure on Venus is over 90 times greater than the atmospheric pressure on Earth. Which statements are true about boiling water on Venus? Choose the two statements that apply.

Water will boil at a higher temperature on Venus than on Earth. The temperature of water will remain constant while it boils.

Which process is an example of a physical change?

carrots are cut into small pieces and mixed into a salad

The element silver has both physical and chemical properties, some of which do not change when the size of the sample changes. Which of these choices is a physical property that does not change when the size of the sample changes?

density

Sierra helps her father install an air purifier in her house. What type of separation method does an air purifier use to remove dust and allergens from the air?

filtration

How is density calculated?

mass divided by volume

Some properties, such as mass, depend on how much matter is present. Other properties, such as malleability, remain the same no matter how much matter is present. Which of these choices is a physical property of the element potassium that remains the same no matter how much matter is present?

melting point

A statue and a coin are made out of exactly the same materials. Which property would you claim will likely be the same for both the statue and the coin?

reactivity

When paper is burned, the mass of the remaining ash is less than the mass of the original paper. Which reasoning best explains this result?

some of the products of the reaction were given off as a gas

Amanda dropped a rock into a graduated cylinder containing water. The water level in the cylinder increased. Which property of the rock is this experiment designed to measure?

volume

A metal coin has certain properties that can be measured. Which property of a coin is different on the moon than it is on Earth?

weight

Apollo 17 astronauts Eugene Cernan and Harrison Schmitt collected the last samples of moon rocks to bring back to Earth in 1972. The astronauts took measurements of the moon rocks using three categories not affected by gravity. This is because the Earth and moon have different forces of gravity. Which measurement did they not use?

weight

Michael's car ran over a nail, which made a hole in one of the tires. At what point will air stop pouring out of the hole in the tire?

when the air pressure in the tire is equal to atmospheric pressure