Question

difference between physical and chemical change ​

Answer 1

Answer:

Physical change:

1)Can be either reversible or irreversible

2)A physical change affects only the physical properties of a substance.(Size,Shape,State)

3)No new substance is formed

4)The substance after the change and the substance before the change are same chemically.

Chemical Change:

1)There may be change in colour

2)Evolution of gas or effervescence may be observed

3) A precipitate(solid substance formed from a liquid) may be formed

4)Heat may be given out(exothermic)

or absorbed (endothermic)

Explanation:

Answer 2

$\fbox{ \fbox{ \bold { \: \huge{ Physical \: Change \: : - }}}}$

$\bold{\large{ (1)\: in \: a \: physical \: change \: , \: the \: molecules \: are \: rearranged \: while \: their \: actual \: composition \: remains \: same \: }}$

$\bold{ \large{ (2)\: physical \: change \: is \: easily \: reversible \: i.e \: original \: substance \: can \: be \: recovered \: }}$

$\bold{\large{ (3)\: physical \: change \: is \: a \: temporary \: change \: }}$

$\fbox{ \fbox{\bold{ \huge{ \: Chemical \: Change \: : - }}}}$

$\bold{\large{ (1)\: in \: a \: chemical \: change \: , \: the \: molecular \: composition \: of \: a \: substance \: completely \: changes \: and \: a \: new \: substance \: is \: formed</p><p> \: }}$

$\bold{\large{ (2) \: chemical \: change \: is \: irreversible \: i.e \: original \: substance \: cannot \: be \: recovered \: }}$

$\bold{ \large{(3) \: chemical \: change \: is \: a \: permanent \: change \: }}$