Which of the following is a chemical change?

Question

ice melting
ice being carved
water boiling
water breaking down into hydrogen and oxygen

Answer 1

"water breaking down into hydrogen and oxygen" is a chemical change!
Physical changes occur when objects undergo a change that does not change their chemical nature. A physical change involves a change in physical properties. Physical properties can be observed without changing the type of matter. Examples of physical properties include: texture, shape, size, color, odor, volume, mass, weight, and density. Like water can be frozen, melted or evaported but it is still water (or H2O)
Chemical changes are changes substances undergo when they become new or different substances. For example, the fireworks we see on the 4th of July are actually metals such as magnesium and copper that change chemically as they light up the night skies with their fantastic colors. To identify a chemical change look for observable signs such as color change, bubbling and fizzing, light production, smoke, and presence of heat. Also when oxygen and hydrogen split its a chemical change because you do not have water (or H2O) anymore you have to seperate elements: hydrogen and oxygen.

A last example showing a differance between a chemical and phyical change is paper. If you rip paper its still paper so its a physical change, but if you burn paper its a chemical because you don't have paper anymore and also because you can't turn the ashes back into paper.

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Answer 2

Water breaking down into hydrogen and oxygen. The rest can easily be reversed and are therefore physical changes.

Answer 3

cooknig a steak......it variations after affected. paper looks the comparable no count number what number circumstances you tear it. boiling water would not because of the fact it nonetheless looks the comparable, and it does lower back to the comparable timp after it boils

Answer 4

breaking down of course!