Answer:
The answer is melting and freezing point.
Explanation:
First calculate number of Nitrogen atoms contained by 1 mole of Zn(NO₃)₂,
As one formula unit of Zn(NO₃)₂ contains 2 Nitrogen atoms, then one mole of Zn(NO₃)₂ will contain,
= 2 × 6.022 × 10²³
= 1.20 × 10²⁴ Atoms of Nitrogen / mole
Now, calculate number of Nitrogen Atoms in 0.150 moles of Zn(NO₃)₂.
As,
1 mole of Zn(NO₃)₂ contained = 1.20 × 10²⁴ atoms of N
Then,
0.15 mole of Zn(NO₃)₂ will contain = X atoms of N
Solving for X,
X = (0.15 mol × 1.20 × 10²⁴ atom) ÷ 1 mol
X = 1.80 × 10²⁴ Atoms of Nitrogen
Result:
So, 0.15 mole of Zn(NO₃)₂ contains 1.80 × 10²⁴ atoms of Nitrogen.
B. stars form large groupings
Solutions are made up of two non reacting species called solute and solvent. The amount of solute in solvent is known as concentration of that solute. Concentration is often measured in Molarity. Molarity is the amount of solute dissolved in 1 dm3 of solution. Answer to your question is as follow;
Answer: (A)
(B) 
Explanation:
(A) As we know that HCl is a strong acid and when it is added to an aqueous solution then it leads to increase in the concentration of hydrogen ions. And, when an acid or base is added to a solution then any resistance by the solution in changing the pH of the solution is known as a buffer.
This means that addition of buffer into the given solution will not cause much change in the concentration of
in large amount.
As both the buffer components are salt then they will remain dissociated as follows.
Hence, net ionic equation will be as follows.
(B) When we add small amount of sodium hydroxide into the solution then there will occur an increase in concentration of hydroxide ions into the solution. But then due to the presence of buffer there will occur not much change in concentration and the acid will get converted into salt.
The net ionic equation is as follows.
