a pack of baking powder ( a raising agent) contains sodium hydrogencarbonate , tartaric acid and rice starch.

a. write an equation for the action of heat on sodium hydrogencarbonate.

b. suggest a reason for the presence of tartaric acid in the mixture.

c. describe a test you would carry out to indicate the presence of rice starch in the mixture.

Question

a pack of baking powder ( a raising agent) contains sodium hydrogencarbonate , tartaric acid and rice starch.

a. write an equation for the action of heat on sodium hydrogencarbonate.

b. suggest a reason for the presence of tartaric acid in the mixture.

c. describe a test you would carry out to indicate the presence of rice starch in the mixture.

anonymous · Answer

a. 2NaHCO3 ---> Na2CO3 + CO2 + H2O

matt101 · Answer

a) When dissolved in water, sodium hydrogen carbonate (sodium bicarbonate) dissociates into a sodium ion and a bicarbonate ion. Heat will cause bicarbonate to decompose as follows:

$$HCO_3^- \rightarrow CO_2+OH^-$$
b) The reaction above would explain why tartaric acid is present in the mixture - it would neutralize the hydroxide ions that are formed as a result.

c) Is there a specific kind of test you learned about?