Where’s the chart and scientists?
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.
No, there’s not any pressure
The moles of HCl to neutralize the sodium hydroxide produced is<u> 0.0135 mole. </u>
Neutralization or neutralization is a chemical response wherein an acid and a base react quantitatively with each other. In a reaction in water, neutralization outcomes in there being no excess of hydrogen or hydroxide ions gift in the answer.
<u>calculation:-</u>
<u />
2Na + 2H₂O -----> 2NaOH + H₂
2 mol or 46g of Na produces 80 grams of NaOH
∴ 0.31 g of Na will produce = 80/46 × 0.31
= 0.54 gram of NaOH.
mol of NaOH = 0.54/40
= 0.0135
Since both Hcl and NaOH have the same valance factor,
1 mole NaOH is needed to neutralize 1 mol HCl
∴ 0.0135 mole of NaOH will need = 0.0135 mole of HCl
mass = 0.0135 × 36.5
=<u> 0.493 grams of HCL.</u>
Learn more about neutralizing here:-brainly.com/question/23008798
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