Answer is: A. 1.1 3 1023 NiCl2 formula units.
m(NiCl₂) = 24.6 g; mass of nickel(II) chloride.
M(NiCl₂) = 129.6 g/mol; molar mass of nickel(II) chloride.
n(NiCl₂) = m(NiCl₂) ÷ M(NiCl₂).
n(NiCl₂) = 24.6 g ÷ 129.6 g/mol.
n(NiCl₂) = 0.19 mol; amount of nickel(II) chloride.
Na = 6.022·10²³ 1/mol; Avogadro constant.
N(NiCl₂) = n(NiCl₂) · Na.
N(NiCl₂) = 0.19 mol · 6.022·10²³ 1/mol.
N(NiCl₂) = 1.13·10²³; number of formula units.
Answer:
The symbol for decimeter is dm
Explanation:
No need for an explanation
The heat of solution is -51.8 kJ/mol
<h3>What is the heat of solution?</h3>
We know that in a calorimeter, there is no loss or gain of energy. It is a good example of a closed system.
Number of moles of KOH = 11.9-g/56 g/mol = 0.21 moles
Temperature rise = 26.0 ∘c
Mass of the water = 100.0 grams
Heat capacity = 4.184 j/g⋅°c
Then;
ΔH = mcθ
ΔH = 100g * 4.184 j/g⋅°c * 26.0 ∘c = 10.88 kJ
Heat of solution = -(10.88 kJ/ 0.21 moles) = -51.8 kJ/mol
Learn more about heat of solution:brainly.com/question/24243878
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In buffer solution there is an equilibrium between the acid HA and its conjugate base A⁻: HA(aq) ⇌ H⁺(aq) + A⁻(aq).
When acid (H⁺ ions) is added to the buffer solution, the equilibrium is shifted to the left, because conjugate base (A⁻) reacts with hydrogen cations from added acid, according to Le Chatelier's principle: H⁺(aq) + A⁻(aq) ⇄ HA(aq). So, the conjugate base (A⁻) consumes some hydrogen cations and pH is not decreasing (less H⁺ ions, higher pH of solution).
A buffer can be defined as a substance that prevents the pH of a solution from changing by either releasing or absorbing H⁺ in a solution.
Buffer is a solution that can resist pH change upon the addition of an acidic or basic components and it is able to neutralize small amounts of added acid or base, pH of the solution is relatively stable
