Calculate the pH of a 0.35 mol/L solution of butanoic acid

2.6

Explanation:

Step 1: Given and required data

Step 2: Calculate the acid dissociation constant (Ka) of butanoic acid

We will use the following expression.

pKa = -log Ka

Ka = antilog - pKa

Ka = antilog -4.82 = 1.51 × 10⁻⁵

Step 3: Calculate [H⁺] of the solution

For a weak acid, we can use the following expression.

[H⁺] = √(Ca × Ka)

[H⁺] = √(0.35 × 1.51 × 10⁻⁵) = 2.3 × 10⁻³ M

Step 4: Calculate the pH of the solution

pH = -log [H⁺] = -log 2.3 × 10⁻³ = 2.6

the best answer is d because the strong cohesion is caused by the ability of water molecules to undergo hydrogen bonding.

a is incorrect because when water solidifies, it becomes   ice, which expands and occupies a bigger volume for the same mass of water in its liquid state.

b is incorrect because water has high surface tension. besides bonding to itself it hydrogen bonds to other molecules at the top decreasing possibility for breaking of attractive forces.

c is incorrect because the water molecule has oxygen which is highly electronegative and so pulls the electron pair towards itself creating a dipole moment, making the molecule polar.

e is incorrect because water has strong adhesion, ability to stick to other molecules such as glass because of this molecules having stronger hydrogen bonding than water.

answer:

technetium is the most reactive. this is followed by silver. the least reactive out of these three elements is strontium.