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3 years ago

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You are given a solution of hcooh (formic acid) with an approximate concentration of 0.20 m and you will titrate this with a 0.1

105 m naoh. you add 20.00 ml of hcooh to the beaker before titrating, and it requires 35.43 ml of naoh to reach the end point. what is the concentration of the hcooh solution?

2 answers:

Kruka [31]3 years ago

7 0

Answer: 0.1958 M

Explanation:

Molarity of a solution is defined as the number of moles of solute dissolved per Liter of the solution.

$HCOOH+NaOH\rightarrow HCOONa+H_2O$

According to the neutralization law,:

$n_1M_1V_1=n_2M_2V_2$

where,

$M_1$ = molarity of $HCOOH$ solution = ?

$V_1$ = volume of $HCOOH$ solution = 20.00 ml

$M_2$ = molarity of $NaOH$ solution = 0.1105 M

$V_2$ = volume of $NaOH$ solution = 35.43 ml

$n_1$ = valency of $HCOOH$ = 1

$n_2$ = valency of $NaOH$ = 1

$1\times M_1\times 20.00=1\times 0.1105\times 35.43$

$M_1=0.1958$

Therefore, the concentration of the $HCOOH$ is 0.1958 M

balu736 [363]3 years ago

6 0

V(NaOH)*M(NaOH)=V(HCOOH)M(HCOOH)
35.43ml*0.1150m=20.00ml*M(HCOOH)
M(HCOOH)=0.2037m

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