MS Science Test 12 ('23-'24)_ Feb 17,'24

Juanita and Olivia set up an experiment to test the viscosity of different liquids. They gathered 10

identical graduated cylinders (100 ml). The girls filled the cylinders with 10 different liquids to the

80 ml mark and then one at a time, dropped a small metal ball in the cylinder. They then measured

the time it took for the ball to drop to the bottom of the cylinder to the nearest hundredth of a

second. The results of their experiment are in this chart.

What liquid type had the highest viscosity?

• cylinder J

• cylinder H

• cylinder A

• cylinder E

What could the girls have done to make their experiment have more reliable data?

• Have different people time the ball dropping for each liquid.

• Round the times off to the nearest second to make it easier.

• Try dropping the ball different ways each time.

• Repeat the experiment to have multiple trials.

Halfway through the experiment, Olivia’s mom said it was time for lunch. The girls put the cylinders in the refrigerator while they went to go eat lunch. When they returned, they finished timing the rest of the balls dropping in the cylinders. Did cooling the cylinders change or cause a problem with their experiment?

• No, this will not change the results of their experiment at all.

• Maybe, there is no way to tell so it should be OK.

• Yes, viscosity can be affected by change in temperature. They should start over and keep the temperature the same for all the cylinders.

• No, it was a good idea to put the cylinders in the refrigerator so the perishable liquids would not spoil while they were at lunch.

Olivia noticed that one of the cylinders was taking a lot longer than the others for the ball to drop through it. She decided to cover the top and then shake up the liquid to see if that would change the time. It did! The ball dropped must faster after she shook the cylinder. What is a reasonable explanation to why this happened?

• When Olivia shook the cylinder, she caused the molecules in the substance to move slower which also caused the ball to move faster.

• When Olivia shook the cylinder, she caused the liquid to have a chemical reaction which changed the substance and therefore, changed its viscosity.

• When Olivia shook the cylinder, she caused a stress called “shear thinning” which lowered the viscosity of the fluid.

• When Olivia shook the cylinder, some of the liquid squirted out and thus changed the viscosity of the fluid.

What is a low-lying landform that is created by deposition of sediment that was carried there by a river when it flows into a larger body of water?

• aquifer

• delta

• water table

• tributary

Loose material that is left behind after the natural breakdown of living things (usually in the early stages of decay) is called what?

• detritus

• delta

• hypoxia

• halophyte

A species that defines a trait of the environment including an environmental condition such as pollution or a disease outbreak is called what?

• indicator species

• invasive species

• keystone species

• all of these

Normally, human beings have a total of how many chromosomes?

• 48 chromosomes

• 24 pairs

• 46 chromosomes

• both A and B

What organelle in a plant cell is the location of the process of photosynthesis?

• vacuole

• chloroplast

• cell wall

• cell membrane

Clues: organelle, found in the nucleus of a cell, responsible for making ribosomes. What is it?

• mitochondrion

• nucleolus

• nuclear membrane

• proteins