Substances can undergo physical changes or chemical changes. what is the difference between these two kinds of changes

2 answers:

8 0

Physical changes are those change which just externally or physically change the state of the object . for example : water boils and evaporates... here the state is just changing from liquid to vapour while the composition is the same.

chemical changes are those which bring about a change in the composition of a substance. for example: burning of paper changes into ash .

slamgirl [31]3 years ago

6 0

There are several differences between a physical and chemical change in matter or substances. A physical change in a substance doesn't change what the substance is. In a chemical change where there is a chemical reaction, a new substance is formed and energy is either given off or absorbed.

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Vladimir79 [104]

Answer:

The answer is " $1.01 \times 10^{-13}$ "

Explanation:

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$KE=U=\frac{kqq'}{r}\\\\$

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$\to r=\frac{kqq'}{KE}\\\\$

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