Question

1. calculate the volume in milliliters of a 1.420 m naoh solution required to titrate 25.00 ml of a 4.500 m h₂so₄ solution. h₂so₄(aq) + 2 naoh(aq) → na₂so₄(aq) + 2h₂o(l) a. 127.2 ml b. 115.4 ml c. 187.6 ml d. 158.5 ml e. 194.3 ml

Explanation:

Step1: Calculate the moles of \(H_2SO_4\)

Use the formula \(n = M\times V\) (where \(n\) is moles, \(M\) is molarity, \(V\) is volume in liters).
\(V_{H_2SO_4}=25.00\space mL = 0.02500\space L\), \(M_{H_2SO_4}=4.500\space M\)
\(n_{H_2SO_4}=4.500\times0.02500 = 0.1125\space mol\)

Step2: Determine the moles of \(NaOH\) using the stoichiometry

From the balanced equation \(H_2SO_4(aq)+2NaOH(aq)\to Na_2SO_4(aq) + 2H_2O(l)\), the mole ratio of \(H_2SO_4:NaOH = 1:2\)
\(n_{NaOH}=2\times n_{H_2SO_4}\)
\(n_{NaOH}=2\times0.1125=0.225\space mol\)

Step3: Calculate the volume of \(NaOH\) solution

Use the formula \(V=\frac{n}{M}\) (where \(V\) is volume in liters, \(n\) is moles, \(M\) is molarity)
\(M_{NaOH} = 1.420\space M\), \(n_{NaOH}=0.225\space mol\)
\(V_{NaOH}=\frac{0.225}{1.420}\approx0.1585\space L\)
Convert liters to milliliters: \(V_{NaOH}=0.1585\times1000 = 158.5\space mL\)

Answer:

D. \(158.5\space mL\)