Calculate the volumeof 1.0M NaOH necessary to completely neutralize 100mL of 0.50M of phosphoric acid (H3PO4)?

50 mL

Explanation:

In case of titration , the following formula is used -

M₁V₁ = M₂V₂

where ,

M₁ = concentration of acid ,

V₁ = volume of acid ,

M₂ = concentration of base,

V₂ = volume of base .

from , the question ,

M₁ =  0.50M

V₁ = 100 mL

M₂ =  1.0M

V₂ = ?

Using the above formula , the volume of base , can be calculated as ,

M₁V₁ = M₂V₂

substituting the respective values ,

0.50M * 100 mL =  1.0M * V₂  

V₂  = 50 mL

"record the time to complete a chemical reaction" would most likely be part of a lab procedure.