The first one is B because it’s gonna be positive if it’s gaining energy
Answer:
Ammonia is easily made in the laboratory by heating an ammonium salt, such as ammonium chloride NH4Cl with a strong alkali, such as sodium hydroxide or calcium hydroxide.
The gas may also be made by warming concentrated ammonium hydroxide.
Explanation:
2NH4Cl + Ca(OH)2 → CaCl2 + 2H2O + 2NH3(g)
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.
Question 1 answer: A
Question 2 answer: H
Question 3 answer: J
Question 4 answer: T
