c) the salt solubility decreases with temperature.
Salts usually dissolve in water at a given temperature. When water cannot dissolve anymore salt at that same temperature, it is known as a saturation point. With most substances the solubility increases with increase in temperature. Same is the case for a salt like potassium nitrate. With increase in temperature the ability of it to dissolve in water increases. And so with decrease in temperature, the solubility decreases.
Molar mass NaOH = 40.0 g/mol
Volume in liters of solution :
5 mL / 1000 => 0.005 L
number of moles :
4 / 40 => 0.1 moles
M = n / V
M = 0.1 / 0.005
= 20 mol/L or 20 M
hope this helps!
For 1 mole of S₂O₃²⁻ 0.5 mole of S₂O₈²⁻ will be used.
<h3>What is a balanced Reaction ?</h3>
A reaction in which the number of atoms in reactants is equal to the number of atoms in the products is called a balanced reaction.
The reaction given in the question is
S₂O₈²⁻ + 2I⁻ ⇄ 2SO₄²⁻ + I₂
I₂ + 2S₂O₃²⁻ ⇄ 2I⁻ + S₄O₆²⁻
Adding the equation will give balance equation
S₂O₈²⁻ + 2I⁻ + 2S₂O₃²⁻ ⇄ 2SO₄²⁻ + 2I⁻ + S₄O₆²⁻
So x moles of S₂O₈²⁻ require 2x of S₂O₃²⁻
for 1 mole of S₂O₃²⁻ 0.5 mole of S₂O₈²⁻ will be used.
To know more about Balanced Reaction
brainly.com/question/14280002
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