1.
Density is the relationship between ____. (1 point)
mass and volume
cubic centimeters and pounds
weight and volume
grams and mass
2.
Which of the following is NOT a possible sign of a chemical change? (1 point)
a change in state
a change in color
the release of a gas
the release of energy
3.
Which of the following is true about an object that floats in water? (1 point)
The object is less dense than frozen water.
The mass of the object is less than that of water.
The density of the object is less than that of water.
The volume of the water is greater than the object’s volume.
4.
Three examples of physical change are ____. (1 point)
boiling water, a nail rusting, and a melting candle
a pond freezing, breaking glass, and a burning candle
melting ice, mowing the lawn, and carving a statue
applying lipstick, making lemonade, and baking bread
5.
Suppose a customer brings a gold bracelet to a jeweler and asks for it to be changed into a gold ring. Which of the following is true? (1 point)
The physical property of color will be changed.
The bracelet will go through a chemical change.
The composition of the bracelet will change.
The shape of the gold will change physically.
6.
Which of the following explains how water causes rocks to weather? (1 point)
Water can melt rock material.
Water freezes in the cracks and expands, causing breaks.
Water reacts with the rock and produces gases.
all of the above
7.
How can you tell that the fireworks exploding during a Fourth of July display do not all contain the same ingredients? (1 point)
different colors of explosions
different shapes of explosions
different timing of explosions
all of the above
8.
Which of the following explains why the chemical products from a reaction have a different mass than the chemicals at the beginning? (1 point)
The products are heavier and sink.
The products are lighter and rise.
The products are a gas and escape into the air.
The products are a solid and have more mass.
My answers:
1. mass and volume
2. a change in state
3. The density of the object is less than that of water.
4. melting ice, mowing the lawn, and carving a statue
5. The shape of the gold will change physically.
6. Water freezes in the cracks and expands, causing breaks.
7. all of the above
8. The products are lighter and rise.
please help ASAP!
8 Is wrong. It's the second one. The others are right.
1. Correct! Density is the relationship between mass and volume. To calculate density, you divide the mass of an object by its volume.
2. Incorrect. The correct answer is "a change in state." A change in state, such as from a solid to a liquid or a gas, is a physical change, not a chemical change. The other options listed (change in color, release of a gas, release of energy) are all possible signs of a chemical change.
3. Incorrect. The correct answer is "The object is less dense than frozen water." An object that floats in water is less dense than water itself. If the object were more dense than water, it would sink.
4. Incorrect. The correct answer is "boiling water, a nail rusting, and a melting candle." These are examples of physical changes. The other options listed involve chemical changes.
5. Incorrect. The correct answer is "The composition of the bracelet will change." When the gold bracelet is changed into a gold ring, it undergoes a physical change in shape, but there is no change in its chemical composition.
6. Correct! Water freezing in the cracks of rocks and expanding is a common cause of weathering. As the water freezes and expands, it exerts pressure on the rocks, causing them to break apart over time.
7. Incorrect. The correct answer is "all of the above." Fireworks are made with different ingredients, which result in different colors and shapes of explosions. Additionally, fireworks may be timed differently, adding to the variety in displays.
8. Incorrect. The correct answer is "The products are a gas and escape into the air." During a chemical reaction, new substances are formed, which may be in the form of a gas. If the products are a gas, they can escape into the air, causing a difference in mass compared to the chemicals at the beginning of the reaction.