Question

4. What volume, in cm', of 0. 100 moldm³ H₂SO, will produce an acid salt using 50.00cm³ of 0.200 moldm³ KOH solution? -3 C 75.00 D. 100.00 A. 25.00 B. 50.00 C 75.00​

Answer 1

50.00 cm³

Step-by-step explanation:

Relevant formula:

n = V × c

n = number of moles (mol)

V = volume (dm³)

c = concentration (mol/dm³)

1. Work out moles of KOH

V = 50cm³ = 0.05dm³

Note: remember to convert to the right units (1 dm³ = 1000cm³)

c = 0.2

n = 0.05 × 0.2

n = 0.01

2. Use balanced reaction equation to find the moles of H2SO4

c = 0.1

H2SO4 + 2KOH --> K2SO4 + 2H2O

Ratio of KOH to H2SO4:

2 : 1 (--> 1 is ½ of 2)

If we have 0.01 moles of KOH therefore:

0.01 : x

x = 0.005 (i.e. ½ of 0.01)

3. Calculate volume of H2SO4

n = V × c

0.005 = V × 0.1

V = 0.005 ÷ 0.1

V = 0.05

This reaction will take 0.05 dm³ of H2SO4, or 50 cm³