Answer:
C.) HOCl Ka=3.5x10^-8
Explanation:
In order to a construct a buffer of pH= 7.0 we need to find the pKa values of all the acids given below
we Know that
pKa= -log(Ka)
therefore
A) pKa of HClO2 = -log(1.2 x 10^-2)
=1.9208
B) similarly PKa of HF= -log(7.2 x 1 0^-4)= 2.7644
C) pKa of HOCl= -log(3.5 x 1 0^-8)= 7.45
D) pKa of HCN = -log(4 x 1 0^-10)= 9.3979
If we consider the Henderson- Hasselbalch equation for the calculation of the pH of the buffer solution
The weak acid for making the buffer must have a pKa value near to the desired pH of the weak acid.
So, near to value, pH=7.0. , the only option is HOCl whose pKa value is 7.45.
Hence, HOCl will be chosen for buffer construction.
Given:
Diprotic weak acid H2A:
Ka1 = 3.2 x 10^-6
Ka2 = 6.1 x 10^-9.
Concentration = 0.0650 m
Balanced chemical equation:
H2A ===> 2H+ + A2-
0.0650 0 0
-x 2x x
------------------------------
0.065 - x 2x x
ka1 = 3.2 x 10^-6 = [2x]^2 * [x] / (0.065 - x)
solve for x and determine the concentration at equilibrium.
Answer for your question is;
2,6 = 8
The first shell is 2 electrons the other shell is 6 electrons
Answer:
heat can move from any source but if we are being legitimate it moves from convection
Explanation:
Answer:
The number of atoms in the gemstones of that tiara is
.
Explanation:
Number of diamonds ion tiara = 888
Mass of each diamond = 1.0 carat = 0.200 g (given)
Mass of 888 diamonds in tiara:

Given that diamond is a form of carbon.
Atomic mass of carbon atom = 12 g/mol
Moles of 77.600 g of carbon =
Number of atoms of carbon 14.800 moles:

The number of atoms in the gemstones of that tiara is
.