A triple beam balance is used to measure mass
Percentage recovery gives us an idea of the amount of pure substance recovered after the chemical reaction. Percentage recovery can be more than 100 % or less than 100 %. Usually, in any experiment performed the weight percentage recovery will be less than 100. Percent recovery values greater than 100 show that the recovered compound is contaminated.
Amount of acetaminophen initially taken = 350 mg
Amount of acetaminophen obtained after recovery =185 mg

= 
= 52.9%
Answer:
1 x 10^-12 mol dm^-3
Explanation:
[H+] = 10 ^ -pH
Therefore, pH 12 = 1 x 10^-12 hydrogen ion concentration