Answer:
10.7 g of KOH
Explanation:
First of all, we determine the reaction:
2K (s) + 2H₂O(l) → H₂(g) + 2KOH(aq)
We convert the mass of K, to moles → 7.5 g . mol/39.1 g = 0.192 moles
Ratio is 2:2, so the moles I have of K must produce the same moles of KOH. In this case, the produces moles of KOH are 0.192 moles.
We convert the moles to mass, to finish the answer:
0.192 mol . 56.1g /1mol = 10.7 g of KOH
The answer is D.1.950 g
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Answer:
pH = 2,4
Explanation:
pH is defined as a measure of acidity or alkalinity of a solution based on H⁺ concentration
The HCl dissociates in water thus:
HCl → H⁺ + Cl⁻
That means that moles of HCl are the same than H⁺.
0,35gHCl
= 9,6x10⁻³ moles HCl ≡ moles H⁺
H⁺ molarity is: 
= 3,84x10⁻³M
As pH = -log [H⁺]
<em>pH = 2,4</em>
I hope it helps!
