An unknown weak acid with a concentration of 0.440 M has a pH of 5.600. What is the Ka of the weak acid?

1.43 × 10⁻¹¹

Explanation:

Step 1: Given data

Step 2: Calculate the concentration of H⁺

We will use the definition of pH.

pH = -log [H⁺]

[H⁺] = antilog -pH = antilog -5.600 = 2.512 × 10⁻⁶ M

Step 3: Calculate the acid dissociation constant (Ka)

For a weak acid, we can calculate Ka using the following expression.

Ka = [H⁺]²/Ca

Ka = (2.512 × 10⁻⁶)²/0.440 = 1.43 × 10⁻¹¹

a

explanation:

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.