An aqueous solution is produced by dissolving 1.5 g of barium hydroxide (Ba(OH)2(aq) in enough water to make 0.250 L.
a) write the dissociation reaction of barium hydroxide
b) calculate the molar concentration of OH(aq)
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c) calculate pH

A. Ba(OH)₂ (aq) <==> Ba²⁺ (aq) + 2OH¯ (aq)

B. The molar concentration of OH¯ is 0.072 M

C. The pH of the solution is 12.86

Explanation:

A. Dissociation equation

Barium hydroxide Ba(OH)₂ dissolves in water by the following equation:

Ba(OH)₂ (aq) <==> Ba²⁺ (aq) + 2OH¯ (aq)

B. Determination of the molar concentration of OH¯.

We'll begin by calculating the number of mole in 1.5 g of Ba(OH)₂. This can be obtained as follow:

Mass of Ba(OH)₂ = 1.5 g

Molar mass of Ba(OH)₂ = 137 + 2(16 + 1)

= 137 + 2(17)

= 137 + 34

= 171 g/mol

Mole of Ba(OH)₂ =?

Mole = mass / Molar mass

Mole of Ba(OH)₂ = 1.5 / 171

Mole of Ba(OH)₂ = 0.009 mole

Next, we shall determine the molarity of Ba(OH)₂. This can be obtained as follow:

Mole of Ba(OH)₂ = 0.009 mole

Volume of solution = 0.250 L

Molarity of Ba(OH)₂ =?

Molarity = mole / Volume

Molarity of Ba(OH)₂ = 0.009 / 0.250

Molarity of Ba(OH)₂ = 0.036 M

Finally, we shall determine the molar concentration of OH¯.this can be obtained as follow:

Ba(OH)₂ (aq) <==> Ba²⁺ (aq) + 2OH¯ (aq)

From the balanced equation above,

1 mole of Ba(OH)₂ produced 2 moles OH¯.

Therefore, 0.036 M Ba(OH)₂ will produce = 0.036 × 2 = 0.072 M OH¯.

Therefore, the molar concentration of OH¯ is 0.072 M

C. Determination of the pH.

We'll begin by calculating the pOH of the solution. This can be obtained as follow:

Concentration of OH¯, [OH¯] = 0.072 M

pOH =?

pOH = –Log [OH¯]

pOH = –Log 0.072

pOH = 1.14

Finally, we shall determine the pH. This can be obtained as follow:

pOH = 1.14

pH =?

pH + pOH = 14

pH + 1.14 = 14

Collect like terms

pH = 14 – 1.14

pH = 12.86

in 1783 cavendish was working with his hydrogen gas and found that when he burned it and condensed the vapor it was water. this was very significant since it disproved the greek theory of elements completely since water was not a simple substance but the product of two gases. it was lavoisier who hearing of the experiment gave cavendish's gas the name hydrogen ("water-producer") and added that hydrogen burned by combining with oxygen and that water was a hydrogen-oxygen combination.

explanation:

> b takes place in the gas phase in an isothermal tubular reactor. the feed is one mole of a per one mole of c, an inert. the entering temperature and pressure are 427°c and 10 atm, respectively. the gas constant r = 0.08206 atm · l/mol · k.