Properties of Water, Acid and Bases ReTestt

Plant cells carry water throughout the plant from the roots to the leaves. Which of the following is important for the transport of water in plants?

• Cohesion because it helps water move upward through the plant.

• Adhesion because water molecules stick to the walls of the plant's cell walls.

• Cohesion because it helps water molecules stick together in the plant.

• Adhesion because water molecules are pulled downward to the roots.

The Japanese yen coins are made of aluminum and will float when placed in water. American coins are not made of aluminum and will sink when placed in water. Which statement best explains why the yen coin floats in water?

• The lightweight and shape of the yen coin and cohesive force of water molecules at the surface prevents the coin from sinking.

• The lightweight and shape of the yen coin and adhesive forces allow the coin to remain at the water's surface.

• Yen coins are made of aluminum, which is lightweight enough to remain buoyant on the water's surface.

• The yen coin's smooth surface interacts with water molecules, enhancing the surface tension to support the coin.

How does adhesion benefit plants?

• It helps water molecules stick to the surfaces of plant tissues.

• It prevents water loss by holding water molecules near the plant's surface.

• It helps water move through plant tissue and transport nutrients.

• It supports water movement by creating tension at the water's surface.

Why is a small insect, like a water strider, able to walk on the surface of water?

• The insect's waxy coating prevents it from sinking by repelling water.

• The force exerted by the insect is less than the surface tension of the water.

• The insect's legs are attracted to the water molecules.

• The surface tension of the water is less than the mass of the insect.

Water striders are small insects that have an adaptation to live on top of water. The body of the water strider is distributed over the water's surface because of the insect's long, strong, and slender legs. Hairs on the insect's legs repel water and capture air. The insect can be seen on the surface of calm or slow-moving water and prefers places in ponds, vernal pools, and marshes. What is another factor that enables the water strider to move on top of the water?

• The strong interaction at the water's surface creates a tension that supports the insect's weight.

• Water molecules repel air molecules, allowing insects to remain on the surface.

• The legs of the water strider spread its weight evenly across the water surface, enhancing its ability to float.

• Water molecules are attracted to other water molecules creating strong water surface tension for the insects.

What property of water allows droplets to attach to the surface of a leaf?

• Evaporation

• Adhesion

• Cohesion

• Gravity

After washing her car, Maria notices small droplets of water stayed on the windshield instead of sliding off. Maria continues to drive down the road and notices some water droplets begin to slide down the windshield as she gains speed. However, smaller water droplets remain stuck to the surface of the windshield. Part A Which of the following best explains why the smaller water droplets stick to the car windshield?

• Water droplets stick to the windshield due to adhesive forces.

• Water molecules have a shape that allows them to remain stationary.

• Water droplets stick to the windshield due to a balance between gravity and other forces.

• Water molecules repel each other and are pushed toward the surface of the windshield.

After washing her car, Maria notices small droplets of water stayed on the windshield instead of sliding off. Maria continues to drive down the road and notices some water droplets begin to slide down the windshield as she gains speed. However, smaller water droplets remain stuck to the surface of the windshield.

• Larger droplets slide off because gravity overcomes adhesion.

• Smaller droplets stick better because adhesion is stronger than gravity.

• Water adhesion is weaker on smaller droplets due to decreased surface area.

• Adhesive forces are identical for all droplets, regardless of sizeы

Tags

NGSS.MS-PS2-4

Which of the following is a property of adhesion?

• Water droplets begin to collect and form a larger drop.

• Dew drops hanging from the pedals of a flower.

• Water pours out of a glass in a continuous flow.

• Rainwater falling from the sky due to the pull of gravity.

A student is conducting an experiment on surface tension. The student uses two pennies, eye droppers, tap water, and dish soap water for the experiment. The student counts the number of tap water droplets that fill the top of a penny and the number of dish soap water droplets that fill the top of another penny. As the drops are added to the pennies, the student notices the drops on the pennies begin to grow. The student records how many drops stay on each penny before the drops spill over the edge of the penny. The student records the results on the chart below. Results Tap Water: 24 drops Dish Soap Water: 15 drops Which best explains surface tension based on the experiment results?

• A. The tap water had a lower surface tension because the molecules were not cohesive.

• B. The tap water had a higher surface tension because water molecules are strongly cohesive with each other.

• C. The dish soap had a higher surface tension, allowing fewer drops to stay on the penny.

• D. The dish soap had a lower surface tension because it disrupted the cohesion between water molecules.