Question

a.) calculate the pH of a 0.025 Nitric acid solution

b.) calculate the pH of a 0.10 NaOH

c.) a solution prepared by dissolving 0.28 g of lime (CaO) in 1.00 L water to make limewater (Ca(OH)2)

Answer 1

Answer on Question #52491, Chemistry, Inorganic Chemistry

Question: a.) calculate the pH of a 0.025 Nitric acid solution

b.) calculate the pH of a 0.10 NaOH

c.) a solution prepared by dissolving 0.28 g of lime (CaO) in 1.00 L water to make limewater (Ca(OH)2)

Answer:

a) Nitric acid is fully ionized:

$$[H^+] = 0.025M$$ $$pH = -\log_{0.025} = 1.6$$

b) [OH⁻] = 0.1 M

$$pOH = -\log_{0.1} = 1$$ $$pH = 14 - 1 = 13.$$

c) The number of moles of CaO = 0.28 / 56 = 0.005 moles

$$\mathrm{CaO} + \mathrm{H_2O} = \mathrm{Ca(OH)_2}$$

The number of moles of Ca(OH)2 will be 0.005 moles.

1 mole of Ca(OH)2 will have 2 moles of OH⁻ ions, so the number of moles of OH⁻ = 2*0,005=0.01

The concentration of OH⁻ will be 0.01 M

$$pOH = -\log_{0.01} = 2$$ $$pH = 14 - 2 = 12.$$

http://www.AssignmentExpert.com/