7Th Grade Physical Science Benchmark Test

7th Grade Physical Science Benchmark Test Please do not write on this test. Please mark your answers on the answer sheet

Std I Obj 3a ILO 3a 1- The theory that explains the movement of molecules suggests that: a) molecules do not move b) only gas molecules move c) only liquid molecules move d) gas, liquid, and solid molecules move

Std I Obj 1d, 1e ILO 5c, 6c 2- Why is this model (to the right) accepted today as a representation of the atom? a. this model changed as natural laws changed. b. This model shows exactly what an atom looks like. e c. This model has always been the one that was correct. d. This model is based on demonstrated evidence. e

Std I Obj 1d ILO 4f e 3- What aspects of this atomic model are inaccurate? a. The electron cloud should be much farther from the nucleus b. The electron cloud should show electrons in valence shells e c. The electrons should be zinging all over, not just in a perfect circle d. All of the above statements are inaccuracies of this model

Std I Obj 1c, 3b ILO 4f, 4- If significant energy is removed from a liquid, which drawing below shows what the molecules would look like after the energy was removed?

Std I Obj 1e ILO 6d 5- The reason we have had so many models of atoms throughout history is: a. scientists can make 3-D models now b. scientists use better methods now c. scientists have better technology now d. previous scientists were misinformed

Std I Obj 2a, 3d ILO 5b 6- Which of the following technologies allow us to measure the molecular motion of a substance? a. thermometer b. seismograph c. electron microscope d. telescope

Std I Obj 2d, 2e ILO 1a, 4e 7- What happens to the density of a balloon (tied at the bottom) when heat energy is removed: a. The density increases because the volume of the balloon increases b. The density increases because the volume of the balloon decreases c. The density decreases because the mass decreases d. There is no change in density, only in volume Std I Obj 1b, 1e ILO 4b, 6e 8- Which of these statements explains the relationship between atoms and molecules both today, and during the time of J.J. Thompson in the 19th century? a. Molecules combine to form atoms. b. Atoms combine to form molecules. c. Atoms and molecules combine to form elements. d. Atoms and molecules are two words for the same concept.

Std I Obj 3a, 3c ILO 1e, 3d, 6a 9- Several students are designing demonstrations of diffusion. Which of these are evidence that particles move from an area of high concentration to an area of low concentration? a. One student barfs in the hallway, and eventually the smell can be detected in several classrooms. b. One student puts a few drops of Dr. Pepper into a glass of Mountain Dew, and eventually the entire glass becomes brownish-yellow. c. One student notices dust from the baseball field spreading out to cover the football field. d. All of these are evidence of particle motion.

ILO 6a, 6b 10- Cinderella and Snow White are arguing about the best way to clean dried-on gunk off of dishes. Cinderella first conducts research from the Internet on chemicals which can be used to break apart food particles. Snow White asks the maid back at the castle what methods she has used previously to clean dishes. The maid says to use steam. Which princess used a correct scientific method of research? a. Cinderella used the correct method because she used the Internet. b. Cinderella used the correct method because she used chemicals. c. Snow White used the correct method because she used a phase change of matter. d. Both Cinderella and Snow White were correct because there is more than one scientific method.

Std I Obj 3e ILO 5a 11- Why do engineers design and construct railroad tracks with a gap between the metal rails? a. Because the summer heat makes the rails expand b. Because the summer sun makes the rails contract c. Because the winter cold makes the rails expand d. Because the winter cold makes the rails contract

Std I Obj 2a, 2d, 2e ILO 1a, 1e, 4a, 12- A student experimented with a balloon. The empty balloon was massed and the data was recorded as 2.0 grams. The balloon was then inflated and was massed again. This time the mass measured 2.3 grams. What research question is most appropriate for this experiment? a. Can the volume of a gas change? b. Can the mass of a gas change? c. Can the mass of a gas be measured? d. Can the volume of a gas be measured?

Std I Obj 2b ILO 1f 13- An egg sinks in water but floats in salt water. What Inference can you make about the density of the egg? a. It is more dense than water but less dense than salt water. b. It is less dense than water and less dense than salt water c. It is denser than water and denser than salt water. d. It is less dense than water but more dense than salt water. Std I Obj 3a, 3e ILO 6a 14- A metal lid was very tightly screwed onto a glass jar. To get the jar open, Kelly held the lid under hot water. Why was Kelly able to remove the lid? a. Metal particles move more rapidly when heated so the particles moved farther apart, and the lid increased in size slightly. b. Metal particles move less rapidly when heated so the particles moved closer together, and the lid decreased in size slightly. c. The metal particles did not move. The water loosened the lid. d. The metal particles melted because the water was so hot.

Std I Obj 3a, 3c ILO 5a, 6a 15- If a used cat litter box is placed in a closed bathroom over the weekend, then the door to the bathroom is opened which direction will the net movement of “stink” particles go? a. Stink particles will not move, but clean-air particles will come in to make it smell better b. Stink particles will spread out and move out of the bathroom to make it smell better c. Stink particles will stay in the bathroom and it will always stink d. Stink particles will die to make it smell better

Std I Obj 2a 16- Your teacher gives you a small, jagged stone and asks you to calculate its mass and volume. Which instruments would you use in order to make the measurements? a. microscope and graduated cylinder b. graduated cylinder and triple beam balance c. triple beam balance and ruler d. ruler and microscope

Std I Obj 3b, 3c, 3d ILO 6a 17- If it takes a drop of dye 2 minutes to diffuse in room temperature water, approximately how long would it take to diffuse in cold water, and why? a. 2 minutes because water always has the same diffusion rate. b. 2 minutes because molecules of water are in constant motion. c. 30 seconds because the dye would be warmer than the cold water. d. 8 minutes because the molecules of cold water do not have as much energy as warm water.

Std II Obj 1b, 1c ILO 3d 18- Ryan is given the following items: a rock, sand, water, and metal bar. Ryan calculates the density of each object . The results are as follows: Rock = 3.2 g/mL, Sand = 1.9 g/mL, Water = 1.0g/mL, Piece of metal = 6.5 g/mL . Ryan then puts all of the items into a jar and shakes it up. He lets the jar settle for 5 minutes. What would be the expected order of the items going from the top of the container to the bottom?

a. rock, sand, water, metal b. metal, rock, sand, water c. water, sand, rock, metal d. sand, metal, water, rock Std II Obj 1a ILO 3c, 3d 19- You are given an unknown object. You find its mass to be 28g. You find its volume to be 10 mL. Where would this object belong if it were compared to the earth densities below?

a. water b. crust c. mantle d. atmosphere

Earth Layer Approximate Density Water 0.9 - 1.3 g/mL Crust 2.7 – 3.0 g/mL Mantle 3.3 – 5.7 g/mL Outer Core 9.0-12.0 g/mL Inner Core 12.7 – 13.0 g/mL

Std II Obj 2a, 2b ILO 1b 20- Why are iron and nickel found in Earth’s core? a. They have a higher density than most of Earth’s substances. b. They have a lower density than most of Earth’s substances. c. The core is hotter than the other layers of the earth. d. The core is more compact than the other layers of the earth.

Std II Obj 1c, 1d ILO 3c 21- A beach is composed of particles of sand of the same size. Why doesn’t the beach have materials of all sizes? The particles have a. come from the same place. b. come to the beach at the same time. c. been found in underwater canyons. d. been sorted by size and density.

Std II Obj 1c, 1d, 1e ILO 1e 22- Sand with particles of the same size was gently shaken in a jar to see if layers would form. What variable was being tested? a. particle size b. particle density c. particle color d. particle type

Std II Obj 2d ILO 3b 23- Why is a relief globe (with bumps for mountains like the one below) an inacurrate model of earth? a. The globe shows the mountains as too tall in relation to the circumference. b. The globe is tipped slightly sideways. c. The globe distorts the size of the continents at the poles. d. The globe has too many internal layers.

Std II Obj 1c 24- Water is added to a jar with soil in it and the jar is shaken. Which drawing shows what will happen after it sits for several minutes? a. b. c. d.

Std II Obj 1c, 1d ILO 5a 25- A streambed contains round rocks, all about the same size. Why are there no smaller particles of sand and clay? Sand and clay a. are denser. b. have washed away. c. were never there. d. are too small to see.

Std II Obj 2d ILO 5b 26- How has technology influenced our discoveries of the structure of the earth? a. Satellite technology has allowed us to see what is inside the earth b. Infrared (heat sensing) technology has allowed us to measure the temperature of the earth c. X-Ray technology has allowed us to see the rock layers within the earth d. Seismograph (earthquake sensing) technology has allowed us to calculate the thickness and density of the layers within the earth.

Std II Obj 1c, 1d ILO 3a, 5a 27- If you had pieces of rock, all made of the same minerals, and placed them in the center of a fast- moving river, which of these would be carried farthest downstream? a) large boulder b) medium rocks c) pebbles d) particles of sand ……. . Use the following scenario to answer the next two questions:

At the District Science Fair, you notice a display board with a project on skateboards. You are interested because you think skateboarding is cool. The student doing the project listed this as his procedure:

Step 1- gather a skateboard, a 5 kg bag of flour, a 25 kg bag of flour, a bungee cord, & stopwatch Step 2- time the skateboard as it rolls down from the garage door to the gutter on my driveway Step 3- strap the 5 kg bag of flour to the skateboard with the bungee cord Step 4- repeat the timing procedure down the same driveway Step 5- remove the 5 kg bag and strap the 25 kg bag of flour to the skateboard with the bungee Step 6- repeat the timing procedure down the same driveway Step 7- repeat steps 2 through 6 three times

ILO 1a, 1d, 1e, 2b, 6a 28- What variable was this student measuring? (The dependent variable) a. the length of the driveway b. b. the shape of the skateboard c. the speed of the skateboard d. d. the weight of the skateboard

ILO 1e, 1f, 4b, 6b 29- Is this a good experiment design? a. Yes, because the student controlled all of the variables except one b. Yes, because the student tested something with a skateboard c. No, because the student didn’t do the test in a lab. d. No. because the student didn’t conduct background research first.

ILO 1a, 1e, 2d, 3a, 3d, 4d, 6f 30- Which line on the graph shows what happens to molten lava as it cools. Assume that the numbers represent temperature in degrees Celsius.

Lava Temperature (Celsius)

a. Line A b. Line B c. Line C d. none are correct