Which of the following is an example of a chemical change? dissolving sugar in coffee evaporating rubbing alcohol freezing water rusting iron

Rusting iron is an example of a chemical change because iron reacts with air when moisture is present.

examples of chemical changes are:

•Molecules rearrange with other molecules to make new substance

•Can be production of flames

•Color change

•Bubbling/fizzing

•Temp. change

Examples of physical changes are:

•Melting

•Boiling

•Freezing

•Condensing

•Breaking

•Bending

•Dissolving

The answer is Rusting iron

c is having 4 valence electrons and is bonded to three hydrogens and one sulphur atom, therefore, the number of bond pair is equal to four. as all the valence electrons are used in forming the bonds so, there is no lone pair left on carbon.

s is having 6 valence electrons and is bonded to one other sulfur atom and one carbon atom, therefore, the number of bond pair is equal to 2. as only two valence electrons are used in forming the bonds so, four electrons are left. therefore, two lone pairs are present on s.