Question

a 0.090 m solution of a monoprotic acid has a percent dissociation of 0.60 % . part a determine the acid ionization constant (ka) for the acid.

Answer 1

To determine the acid ionization constant (Ka) for the acid, we can use the percent dissociation and the initial concentration of the acid. By applying the formula for Ka, we can solve for the constant.

Step-by-step explanation:

To determine the acid ionization constant (Ka) for the acid, we can use the percent dissociation of the acid. The percent dissociation is the ratio of the concentration of dissociated acid to the initial concentration of the acid, multiplied by 100. In this case, the percent dissociation is 0.60%.

Let's assume the initial concentration of the acid is x M. Given that the percent dissociation is 0.60%, the concentration of dissociated acid is 0.006x M (0.60% of x). Therefore, the concentration of undissociated acid is (1 - 0.006)x M.

The equation for the dissociation of the acid is: HA ⇌ H+ + A-

The acid ionization constant (Ka) can be calculated using the equation: Ka = [H+][A-] / [HA].

Substituting the concentrations, we get Ka = (0.006x)(0.006x) / ((1 - 0.006)x).

Canceling out the x term, we get Ka = 0.006x / (1 - 0.006). Finally, substituting the known values, Ka = 0.006 * 0.090 / (1 - 0.006) = 0.00596.

Answer 2

To calculate the Ka for a monoprotic acid with a percent dissociation of 0.60% in a 0.090 M solution, first determine [H+] concentration, then use the Ka expression Ka = [H+][A-]/[HA], resulting in Ka = 3.24 × 10^-5.

Step-by-step explanation:

To determine the acid ionization constant (Ka) for a monoprotic acid with a percent dissociation of 0.60% in a 0.090 M solution, we first need to calculate the concentration of hydrogen ions (H+) produced by the dissociation of the acid. The percent dissociation is given as a percentage, so we convert this to a decimal by dividing by 100, which gives us 0.006. Multiplying the initial concentration of the acid (0.090 M) by this decimal gives us the concentration of H+ ions (and the conjugate base since it's a monoprotic acid), which is 0.090 M * 0.006 = 0.00054 M.

With this information, we can use the expression for the acid dissociation constant, Ka = [H+][A-]/[HA], where [HA] is the concentration of the undissociated acid, [H+] is the concentration of hydrogen ions, and [A-] is the concentration of the conjugate base. Ka can then be calculated as:

Ka = ([H+]^2) / ([HA] - [H+]) = (0.00054^2) / (0.090 - 0.00054) = 3.24 × 10^-5.