Answer: The kilograms of water must evaporate from 8kg of a 25% salt solution to produce 40% salt solution is 3 kg.
Explanation:
According to the ratio and proportion:
where,
= concentration of ist solution = 25%
= mass of ist solution = 8 kg
= concentration of second solution = 40%
= mass of second solution = ? kg
Thus the final solution must have a mass of 5 kg , i.e (8-5)= 3 kg of mass must be evaporated.
Therefore, the mass that must be evaporated from 8kg of a 25% salt solution to produce 40% salt solution is 3 kg.
Answer:
Explanation:
By definition, <em>half neutralization</em> is the point at which half of the acid has been neutralized.
The neutralization reaction that you are studying is the acid-base reaction:
- HCl (aq) + NaOH (aq) → NaCl(aq) + H₂O (aq)
Then, since the starting molarity of the acid (HCl) is 0.2 M, you just need to find half of that concentration:
- Half molarity = M / 2 = 0.2 M / 2 = 0.1 M
So, the answer is the first choice: a. 0.1 M.
The correct answer is
B.The elements all have three valence electrons
