Answer:
0.50 moles of Cu
Explanation:
The balanced chemical equation for given synthetic reaction is,
2 Cu + S → Cu₂S
According to balance chemical equation,
1 mole of Cu₂S is produced by = 2 moles of Cu
So,
0.25 moles of Cu₂S will be produced by = X moles of Cu
Solving for X,
X = 0.25 mol × 2 mol / 1 mol
X = 0.50 moles of Cu
Hence, as the molar ratio of Cu to Cu₂S is 2:1 hence, to produce 0.25 moles of Cu₂S we will need 0.50 moles of Cu.
Answer: A 0.20 M solution of HCl with a volume of 15.0 mL is exactly neutralized by the 0.10 M solution of NaOH with 3 mL volume.
Explanation:
Given:
= 0.20 M,
= 15.0 mL
= 0.10 M,
= ?
Formula used is as follows.

Substitute the values into above formula s follows.
![M_{1}V_{1} = M_{2}V_{2}\\0.20 M ]times 15.0 mL = 0.10 M ]times V_{2}\\V_{2} = 30 mL](https://tex.z-dn.net/?f=M_%7B1%7DV_%7B1%7D%20%3D%20M_%7B2%7DV_%7B2%7D%5C%5C0.20%20M%20%5Dtimes%2015.0%20mL%20%3D%200.10%20M%20%5Dtimes%20V_%7B2%7D%5C%5CV_%7B2%7D%20%3D%2030%20mL)
Thus, we can conclude that a 0.20 M solution of HCl with a volume of 15.0 mL is exactly neutralized by the 0.10 M solution of NaOH with 3 mL volume.
Answer:
1. KNO3
2. Ca(NO3)2
3. CaCl2
4. KCl
Explanation:
In each of the neutralization reactions, the H from one of the reactant(acid) will combine with the OH from the other reactant (base) to form water while the other elements combine to give the salt as shown below:
1. HNO3 + KOH → H2O + KNO3
The salt produced is KNO3
2. 2HNO3 + Ca(OH)2 → 2H2O + Ca(NO3)2
The salt produced is Ca(NO3)2
3. 2HCl +Ca(OH)2 → 2H2O + CaCl2
The salt produced is CaCl2
4. HCl +KOH → H2O + KCl
The salt produced is KCl