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: Option (C) is the correct answer.
Explanation:
In a substance, the total energy of its molecular motion is known as heat. Whereas when we measure the average energy of molecular motion of a substance then it is known as temperature.
So, any increase or decrease in temperature will lead to change in heat of a substance.
When one mole of a substance is burned then the amount of energy released in the form of heat is known as heat of combustion.
Relation between heat and temperature is as follows.
q = 
Thus, we can conclude that to measure the enthalpy of combustion it cannot be measured, only calculated using the equation; q =
.
Ionic, think about the way metals share electrons with other metals, resulting in malleability.
Answer:
Lead Pb
Explanation:
Firstly, we need to know what occurs when a radioisotope emits an alpha particle. An alpha particle is an helium atom. When an isotope emits an alpha particle, it loses an helium atom corresponding to subtracting 4 from its mass number and 2 from its atomic number. This of course coupled with the release of radiation.
Now, we polonium has a proton number of 84 and a mass number of 210. Subtracting 2 and 4 respectively from its proton and mass numbers will yield 82 and 206 proton and mass numbers respectively.
Hence, the decomposition of the Po-210 isotope will yield an element with 82 proton number and 206 mass number. This corresponds to the element Lead.
210Po ——> 206Pb + alpha particle + radiation
Answer:
rate = kxyz
Explanation:
It is worth knowing that the rate low can only be determined by experimentation only not by just balancing equations. So here we are told that all the reactants x , y and z are all first order. This is important because we use this as exponents. That is why the exponents of all the reactants will be 1.
rate = kxyz