GK
CHEMISTRY
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
heat it
|
|
|
cool it
|
|
|
mix it
|
|
|
freeze it
|
Detailed explanation-1: -Heat helps baking powder produce tiny bubbles of gas, which makes the cake light and fluffy. Heat causes protein from the egg to change and make the cake firm.
Detailed explanation-2: -Dissolving and mixing: Simple forms of dissolving and mixing are considered physical changes, but mixing the ingredients of a cake is not a simple mixing process. A chemical change starts to occur when the ingredients are mixed, forming new substances.
Detailed explanation-3: -The balanced chemical reaction can be given as: 2 NaHCO 3 ( s ) → Na 2 CO 3 ( s ) + H 2 O ( g ) + CO 2 ( g ) ( Sodium bicarbonate ) ( Sodium carbonate ) ( Water ) ( Carbon dioxide ) .
Detailed explanation-4: -The trapped carbon dioxide makes the dough rise, and the alcohol evaporates during the baking process. This is an irreversible chemical change, because by consuming the sugar, the yeast has created new substances-carbon dioxide and ethanol-and the reaction cannot be reversed.