Question
Joshua fills one large container with cold water Then he fills a small container with hot water and red food coloring, and seals it with a lid. Next, he puts the small container into the large container and removes the lid of the small container. He observes the red colored water from the small container rising up to the top of the cold water. Which two statements explain why this happens?(1 point)
Responses
because the hot water is less dense than the cold water
because the hot water is less dense than the cold water
because the hot water has the same density as the cold water
because the hot water has the same density as the cold water
because the hot water molecules move as fast as those of cold water
because the hot water molecules move as fast as those of cold water
because the hot water molecules move faster than those of cold water
because the hot water molecules move faster than those of cold water
because the hot water is more dense than the cold water
because the hot water is more dense than the cold water
The correct statements are:
1. because the hot water is less dense than the cold water
2. because the hot water molecules move faster than those of cold water
When hot water is added to cold water. In which direction does the heat energy move?(1 point)
Responses
No heat energy moves, as it all remains in the hot water.
No heat energy moves, as it all remains in the hot water.
Equivalent amounts of heat energy move in both directions.
Equivalent amounts of heat energy move in both directions.
The heat energy moves from the cold water into the hot water.
The heat energy moves from the cold water into the hot water.
The heat energy moves from the hot water into the cold water
The correct response is: The heat energy moves from the hot water into the cold water.
If a mixture of different gases is heated, it rises to the top of its container. Which statement best explains this result?(1 point)
Responses
Heated gases have lower kinetic energy and higher density.
Heated gases have lower kinetic energy and higher density.
Heated gases have higher kinetic energy and decreased density.
Heated gases have higher kinetic energy and decreased density.
Heated gases have lower kinetic energy and lower density.
Heated gases have lower kinetic energy and lower density.
Heated gases have higher kinetic energy and higher density.
Heated gases have higher kinetic energy and higher density.
The correct response is: Heated gases have higher kinetic energy and decreased density.
The correct statements that explain why the red colored water from the small container rises up to the top of the cold water are:
1. because the hot water is less dense than the cold water
2. because the hot water molecules move faster than those of cold water
The correct statement is:
1. because the hot water is less dense than the cold water
2. because the hot water molecules move faster than those of cold water
Explanation:
The first statement is correct because when the hot water is added to the cold water, its density is lower compared to the cold water. Density is defined as the mass divided by the volume, so a substance with lower density will be lighter for the same volume. Therefore, the hot water will rise up to the top as it is less dense than the cold water.
The second statement is also correct because the molecules in hot water have more energy due to the higher temperature. This extra energy makes the molecules move faster compared to the molecules in cold water. As the hot water molecules move faster, they collide with the molecules in the cold water and transfer some of their energy. This energy transfer causes the molecules in the cold water to move faster, leading to expansion and the rise of the red colored water.