Respuesta :
Answer : The correct options are, (a) and (f)
Explanation :
Chemical change : It is a change where changes occurs in the chemical composition and thus resulting in the formation of new compound or substance. It is an irreversible reaction.
The indication of chemical changes are :
Formation of gas bubbles.
Formation of precipitate.
Change in color.
Change in temperature.
Change in volume.
Change in smell or taste.
Evolution of heat, light and sound.
Physical change : It is a change in which shape and size of a substance changes. In this there is no change in the chemical composition of the substance and no new substance is forming. It is a reversible reaction.
The indication of chemical changes are :
Change in shape.
Change in form.
Change in size.
Change in phase.
(a) Leaves turning color in the fall : It is a chemical change.
(b) Dew forms on a blade of grass : It is a physical change because only changes takes place in the phase from vapor phase to liquid phase.
(c) Ethanol evaporates : It is a physical change because only changes takes place in the phase from liquid phase to vapor phase.
(d) Sugar dissolves in water : It is a physical change because only changes takes place in the phase from solid phase to liquid phase.
(e) Dry ice sublimes : It is a physical change because only changes takes place in the phase from solid phase to vapor phase.
(f) Charcoal burning : It is a chemical change. When charcoal burns, carbon reacts with oxygen to produce carbon dioxide and water as a product.
Hence, the correct options are, (a) and (f)
