Suppose 100 ml of hydrochloric acid is neutralized by exactly 46.9ml of 0.75M lithuim hydroxide . What is the concentration of the hydrochloric acid?

0.0035M

Explanation:

Given parameters

Volume of HCl  = 100mL  = 0.1L

Volume of LiOH = 46.9mL  = 0.0469L

Molarity of LiOH = 0.75M

Unknown:

Concentration of hydrochloric acid = ?

Solution:

The reaction equation is given as;

         HCl   +  LiOH →   LiCl  + H₂O

Let us find the number of moles of the given specie which is LiOH;

   Number of moles  = molarity x volume;

    Number of moles of LiOH = 0.75 x0.0469  = 0.035moles

From the balanced reaction equation;

        1 mole of LiOH combines with 1 mole of HCl

     0.035mole of LiOH will require 0.035mole of HCl

Concentration of HCl =  

 Concentration of HCl  =   = 0.0035M

c. because step up transformer steps up the input voltage i.e increases the input voltage  

the number of turns are greater on the secondary side of step up transformer  

transformer does not handle dc current

it is b that is the answer.