Question

Calculate a reasonable amount (mass in g) of your unknown acid to use for a titration. You will want about 30 mL of titrant to get to the equivalence point. Assume that your base is about 0.05 M and that your unknown acid has a molar mass around 400 g/mol. (Report your answer using 2 significant figures).

Answer 1

Answer:

"0.60 g" is the appropriate solution.

Explanation:

The given values are:

Volume of base,

= 30 ml

Molarity of base,

= 0.05 m

Molar mass of acid,

= 400 g/mol

As we know,

⇒  $Molarity=\frac{Number \ of \ moles \ of \ base}{Number \ of \ solution}$

On substituting the values, we get

⇒           $0.05=\frac{Number \ of \ moles \ of \ base}{30\times 10^{-3}}$

⇒  $Number \ of \ moles \ of \ base=0.05\times 30\times 10^{-3}$

⇒                                             $=1.5\times 10^{-3}$  

hence,

⇒  $Moles \ of \ acid=\frac{Mass \ of \ acid}{Molar \ mass \ of \ acid}$

On substituting the values, we get

⇒  $1.5\times 10^{-3}=\frac{Mass \ of \ acid}{400}$

⇒  $Mass \ of \ acid=1.5\times 10^{-3}\times 400$

⇒                         $=0.60 \ g$