According to the reaction equation:
and by using ICE table:
CN- + H2O ↔ HCN + OH-
initial 0.08 0 0
change -X +X +X
Equ (0.08-X) X X
so from the equilibrium equation, we can get Ka expression
when Ka = [HCN] [OH-]/[CN-]
when Ka = Kw/Kb
= (1 x 10^-14) / (4.9 x 10^-10)
= 2 x 10^-5
So, by substitution:
2 x 10^-5 = X^2 / (0.08 - X)
X= 0.0013
∴ [OH] = X = 0.0013
∴ POH = -㏒[OH]
= -㏒0.0013
= 2.886
∴ PH = 14 - POH
= 14 - 2.886 = 11.11
Answer:
False
Explanation:
The force of gravity is not only determined by the mass of the two objects but also the distance.
The law of universal gravitation states the product of the masses is directly proportional to the gravitational force, but it is also indirectly proportional to the square of the distance between them.
In other words, the greater the masses of each the greater the gravitational force, but the greater the distance between the two, the weaker the gravitational force.
Hope this helps
Answer = Gravity is measured by the acceleration that gives to freely falling objects.