<span>the study of matter and the changes that matter undergoes</span>
The superscript is the atomic mass and the subscript is the atomic number
The problem can be solved using the following formula:
ΔTb = i Kb <em>m</em>
i = moles particles/moles solute
Kb = 0.512 °C/m
m = molality = moles solute/kg solvent
First we can solve for the molality of the solution:
75.0 g ZnCl₂ / 136.286 g/mol = 0.550 mol ZnCl₂
m = 0.550 mol/0.375 kg
m = 1.468 mol/kg
We can now solve for the change in temperature of the boiling point:
ΔTb = i Kb m
ΔTb = (3 mol particles/1 mol ZnCl₂) (0.512 °C/m) (1.468 m)
ΔTb = 2.25 °C
The boiling point of a solution is the initial boiling point plus the change in boiling point:
BP = 100 °C + 2.25 °C
BP = 102.25 °C
The solution will have a boiling point of 102.25 °C.
Answer:
The correct option is;
D. (2)(56 g)
Explanation:
MgCl₂ + 2KOH → Mg(OH)₂ + 2KCl
From the balanced chemical reaction equation, we have;
One mole of MgCl₂ reacts with two moles of KOH to produce one mole of Mg(OH)₂ and 2 moles of KCl
Therefore, the number of moles of KOH that react with one mole of KCl = 2 moles
The mass, m, of the two moles of KOH = Number of moles of KOH × Molar mass of KOH
The molar mass of KOH = 56.1056 g/mol
∴ The mass, m, of the two moles of KOH = 2 moles × 56.1056 g/mol = 112.2112 grams
The amount in grams of KOH that react with one mole of MgCl₂ = 112.2112 grams ≈ 112 grams = (2)(56 g).
Answer:
The concentration of hydroxide ions is 3.02*10⁻³ M
Explanation:
The pOH (or OH potential) is a measure of the basicity or alkalinity of a contamination and is defined as the negative logarithm of the activity of the hydroxide ions. That is, the concentration of OH- ions:
pOH= -log [OH-]
The pOH has a value between 0 and 14 in aqueous solution, the solutions with pOH being greater than 7 being acidic, and those with pOH less than 7 being basic.
If pOH= 2.52 then
2.52= -log [OH-]
[OH-]= 3.02*10⁻³ M
<u><em>The concentration of hydroxide ions is 3.02*10⁻³ M</em></u>
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