2nd Grade Science : 2nd Grade Science

Study concepts, example questions & explanations for 2nd Grade Science

varsity tutors app store varsity tutors android store

Example Questions

Example Question #92 : Physical Science

The photo below is an example of a heating or cooling change that cannot be reversed.

Buttered, Toast, Food, Bread, Margarine

Possible Answers:

False

True

Correct answer:

True

Explanation:

The photo demonstrates a change that cannot be reversed. Once the toast is cooked and the butter melts into it, the changes cannot be reversed. Even if the toast is put into the refrigerator, it will not return to a piece of plain bread. A chemical change has taken place and cannot be reversed.

Example Question #10 : Argue Changes Caused By Heating/Cooling Can't Be Reversed

Which answer choice is a change caused by heating or cooling?

Possible Answers:

Making a salad

Cutting a banana

Baking a cake

Washing your clothes

Correct answer:

Baking a cake

Explanation:

Baking a cake is a change that is caused by heat. The batter is mixed together, and heat is applied to create a chemical change while the food is baking. It cannot be reversed and returned to a mixture or the individual ingredients.

Example Question #1 : Argue Changes Caused By Heating/Cooling Can Be Reversed

An example of a change caused by heating or cooling that can be reversed would be the melting of a crayon and then freezing it back into a solid cube.

Possible Answers:

False

True

Correct answer:

True

Explanation:

The statement above is a true statement and example of how heating and cooling can be reversed. If you melt a crayon, it goes from a solid to a liquid. This can be reversed, and the crayon can be returned to a solid-state by freezing or cooling it. Some changes cannot be reversed, but this example can be reversed.

Example Question #1 : Argue Changes Caused By Heating/Cooling Can Be Reversed

Becca says that some heating changes can be reversed. She gives the example of melting butter. She says that you can turn a solid piece of butter into a liquid and then turn it back to a solid. Her friend Melva disagrees and says butter cannot be changed back and forth.

Who is correct, and why?

Possible Answers:

There is not enough information to tell who is correct.

Melva; she is correct because butter cannot be changed. If the butter is turned into a liquid it cannot be reversed and turned back to a solid.

Neither; both of the girls are wrong

Becca; she is correct because the changes to butter can be reversed. Becca could melt the butter by applying heat and then put it back into the refrigerator to cool it down and make it solid again.

Correct answer:

Becca; she is correct because the changes to butter can be reversed. Becca could melt the butter by applying heat and then put it back into the refrigerator to cool it down and make it solid again.

Explanation:

Butter is an excellent example of a heating change that can be reversed. Becca can melt butter and then cool it to reverse the effects. Melva disagreed with her but is unfortunately wrong in this case. Some heating and cooling changes can be reversed.

Example Question #91 : Physical Science

Which material can be heated or cooled, and then have the changes reversed?

Possible Answers:

Ice cube

Egg

Cake

Bread

Correct answer:

Ice cube

Explanation:

Some objects or materials can be heated or cooled, and the changes caused can be reversed. An ice cube could have the changes applied to it reversed. If you heat an ice cube it will melt, you can refreeze it to turn it back to a solid. If you toast bread, bake a cake, or cook an egg, that change cannot be reversed.

Example Question #2 : Argue Changes Caused By Heating/Cooling Can Be Reversed

Will says some changes caused by heating cannot be reversed. Angelo says some changes can be reversed.

Their father takes a popsicle out of the freezer and sets it on the counter. The popsicle begins to melt. He gets a call and puts it back into the freezer.

Using this example who is correct, Will or Angelo, and why?

Possible Answers:

Will; He is correct because this is a change that cannot be reversed. Once the popsicle has started to melt, there is no changing that.

There is not enough information to decide who is correct.

Angelo; He is correct because this is a change that can be reversed. If the popsicle were melting and put back into the freezer, it would refreeze and become solid again.

Neither of the boys is correct.

Correct answer:

Angelo; He is correct because this is a change that can be reversed. If the popsicle were melting and put back into the freezer, it would refreeze and become solid again.

Explanation:

In the situation presented, Angelo is correct. The changes to the popsicle can be reversed. Once it has been heated up and starts to melt, there is a change. In this case, their father puts it back into the freezer when he gets the call; this would cause the popsicle to refreeze. In some instances, these changes can not be reversed, but in this example, it is possible.

Example Question #241 : 2nd Grade Science

Which photo represents a heating or cooling change that can be reversed?

Possible Answers:

Cake, Piece Of Cake, Confectionery, Bake

Toast, Toaster, Food, White Bread

Fireworks, Pyrotechnics, Fireworks Art

Flame, Candle, Yellow, Wax, Fire, Light

Correct answer:

Flame, Candle, Yellow, Wax, Fire, Light

Explanation:

The photo that represents a heating or cooling change that can be reversed is the candle with melting wax. Once the candle is no longer lit, the wax will reharden and no longer will be a liquid. Baking a cake, heating toast, and lighting fireworks are all examples of applying heat in a way that cannot be reversed.

Example Question #3 : Argue Changes Caused By Heating/Cooling Can Be Reversed

An example of a change caused by heating or cooling that can be reversed would be the melting of a candy bar and then putting it into the refrigerator to reset the chocolate.

Possible Answers:

True

False

Correct answer:

True

Explanation:

The statement above is a true statement and example of how heating and cooling can be reversed. If you melt a candy bar, the chocolate goes from a solid to a liquid. This can be reversed, and the candy bar can be returned to a solid-state by freezing or cooling it. Some changes cannot be reversed, but this example can be reversed.

Example Question #21 : Changes Caused By Heating And Cooling

Which material can be heated or cooled, and then have the changes reversed?

Possible Answers:

Berliner, Breakfast, Bun, Cake, Dessert

Icy, Icicle, Cold, Aviary, Frozen

Marshmallow, Roasted, Toasted, Fire

Buttered, Toast, Food, Bread, Margarine

Correct answer:

Icy, Icicle, Cold, Aviary, Frozen

Explanation:

Some objects or materials can be heated or cooled, and the changes caused can be reversed. Ice could have the changes applied to it reversed. If you heat ice, it will melt, you can refreeze it to turn it back to a solid. If you toast bread, bake a donut, or cook a marshmallow, that change cannot be reversed.

Example Question #102 : Physical Science

Which photo represents a heating or cooling change that can be reversed?

Possible Answers:

Ice, Ice Cream, Ice Cream Flavors

None of the answer choices

Cupcake, Cake, Sweets, Sugar, Carrot

Sunset, Evening, Romantic, Sun

Correct answer:

Ice, Ice Cream, Ice Cream Flavors

Explanation:

The photo that represents a heating or cooling change that can be reversed is melting ice cream. The ice cream could be put back into the freezer, and it would no longer melt and would return to a solid.

Learning Tools by Varsity Tutors