a beaker contains a solution of calcium hydroxide (ca(oh)2) in water. a student places a straw in the beaker…

a beaker contains a solution of calcium hydroxide (ca(oh)2) in water. a student places a straw in the beaker and then breathes into the solution through the straw. as the student breathes into the solution, a white precipitate forms. what is the most likely composition of the precipitate?\no h2o\no caco3\no ch3oh\ndone
Answer
Explanation:
Step1: Identify exhaled gas
When we breathe out, we exhale carbon - dioxide ($CO_2$).
Step2: Consider chemical reaction
$CO_2$ reacts with calcium hydroxide ($Ca(OH)_2$) in the solution. The chemical reaction is $Ca(OH)_2 + CO_2=CaCO_3\downarrow + H_2O$.
Step3: Determine precipitate
The calcium carbonate ($CaCO_3$) formed is insoluble in water and precipitates out.
Answer:
$CaCO_3$