Answer:
Option (2) 2
Explanation:
NO3- + 4H+ + Pb → Pb2+ + NO2 + 2H2O
The equation above can be balance as follow:
There are 3 atoms of the left side and a total of 4 atoms on the right side. It can be balance by putting 2 in front NO3- and 2 in front of NO2 as shown below:
2NO3- + 4H+ + Pb → Pb2+ + 2NO2 + 2H2O
Now the equation is balanced.
The coefficient of NO2 is 2
Answer:
d. is the hydrostatic pressure produced on the surface of a semi-permeable membrane by osmosis.
Explanation:
Osmosis -
It is the flow of the molecules of solvent from a region of higher concentration towards the region of lower concentration via a semipermeable membrane , is known as osmosis.
Osmotic pressure -
It refers to the minimum amount of pressure , which is required to be applied to the solution in order to avoid the flow of pure solvent via the semipermeable membrane , is referred to as osmotic pressure.
Or in simple terms ,
Osmotic pressure is the pressure applied to resists the process of osmosis.
Hence ,
From the given options in the question,
The correct option regarding osmotic pressure is d.
Answer:
The final and initial concentration of the acid and it's conjugate base are approximately equal, that is we use the weak acid approximation.
Explanation:
The Henderson-Hasselbalch is used to calculate the pH of a buffer solution. It depends on the weak acid approximation.
Since the weak acid ionizes only to a small extent, then we can say that [HA] ≈ [HA]i
Where [HA] = final concentration of the acid and [HA]i = initial concentration of the acid.
It also follows that [A^-] ≈ [A^-]i where [A^-] and[A^-]i refer to final and initial concentrations of the conjugate base hence the answer above.
