Question

Scenes A and B depict changes in matter at the atomic scale:

                 

(a) Which show(s) a physical change?

(b) Which show(s) a chemical change?

(c) Which result(s) in different physical properties?

(d) Which result(s) in different chemical p

Answer 1

Solution

$\text{Physical change}$ is a change in which only the physical form of substance is changed (nothing new is created).

$\text{Chemical change}$ is a conversion of one or more substances into a $\text{new substance.}$

$\text{a)}$

Physical change is shown at the picture $\text{a) .}$

We can see the$\text{ change in the form}$ of substance (from solid to gas).

 

$\text{b)}$

Chemical change is shown at the picture $\text{b).}$ We can see the$\text{ formation of bond between two yellow atoms}$ and also the$\text{ formation of bond between two blue atoms.}$

 

$\text{c)}$

$\text{Both chemical and physical change }$can result in different physical properties. So $\text{both pictures}$ show a change in physical properties.

 

$\text{d)}$

$\text{Only chemical change }$can result in different chemical properties. So $\text{only picture b)}$ shows a change in chemical properties.

 

$\text{e)}$Picture $\text{a) }$shows a change in state $\text{(from solid to gas)}$.

Therefore, 

$\text{a)}$ picture a

$\text{b)}$ picture b

$\text{c)}$ both pictures

$\text{d)}$ picture b

$\text{e)}$ picture a