Determine the [H3O+]. Are these solutions acidic or basic?
a. [OH-]=7.0x10^-8 a. [H3O+]= acidic or basic?
b. 0.00030 M Mg[OH]2 b. [H3O+]=acidic or basic?
a)
(H^+)(OH^-) = Kw = 1E-14
You know (OH^-). Calculate (H^+). When (H^+)=(OH^-)=1E-7 M the soln is neutral. If H^+ is greater the OH must be smaller and the soln is acidic. If OH is greater, H must be smaller and the soln is basic.
Indicate whether each of the following is an acidic, basic, or neutral solution:
A) [H3O+] = 6.0*10-12 M
B) [H3O+] = 1.4*10-4 M
C) [OH-] = 5.0*10-12 M
D) [OH-] = 4.5*10-2 M
To determine the [H3O+] (concentration of hydronium ions) and whether these solutions are acidic or basic, we need to use the relationship between [H3O+] and [OH-] (concentration of hydroxide ions) in water.
In pure water, the concentrations of [H3O+] and [OH-] are equal and can be represented as 10^-7 M. Based on this information:
a. [OH-] = 7.0x10^-8 M
To find the [H3O+] concentration, we can use the equation for the ion-product of water:
[H3O+] x [OH-] = 1.0x10^-14 M^2
Rearranging the equation, we have:
[H3O+] = 1.0x10^-14 M^2 / [OH-]
Substituting the given value of [OH-]:
[H3O+] = 1.0x10^-14 M^2 / (7.0x10^-8 M)
Calculating this value:
[H3O+] = 1.43x10^-7 M
Since [H3O+] is greater than [OH-], this solution is acidic.
b. [OH-] = 0.00030 M
Using the same equation as above:
[H3O+] = 1.0x10^-14 M^2 / [OH-]
Substituting the given value of [OH-]:
[H3O+] = 1.0x10^-14 M^2 / (0.00030 M)
Calculating this value:
[H3O+] = 3.33x10^-12 M
Again, since [H3O+] is greater than [OH-], this solution is acidic.
Therefore, both solutions are considered acidic based on the concentration of hydronium ions.