Answer:
Option B is correct.
The net ionic chemical reaction when Cu(NO₃)₂ reacts with water is
Cu²⁺(aq) + H₂O(l) ⇌ Cu(OH)¹⁺(aq) + H¹⁺(aq)
Explanation:
When ions dissolve in polar solvents (in water especially), then often attract ions of opposite signs.
Cu(NO₃)₂ dissolves into Cu²⁺ & NO₃⁻ and water contains H¹⁺ & OH⁻
The Cu²⁺ attracts the OH⁻ from water, thereby giving the Cu(OH)¹⁺ ion (with a net charge of +2-1 = +1) and the NO₃⁻ takes up the H⁺ ion.
I would say there is 10 (2 in the ethyl group, 3 in the three methyl groups and 5 in the pent chain)
In order to balance both of the reactions you need to make sure that both sides of the reaction have the same number of atoms for each atom in order to follow conservation of mass.
KCl+F₂→KF+Cl₂
Notice how in the above reaction there are two chlorine atoms on the products side (right side) and only one atom of chlorine on the reactants side (left side). you want both the reactants and products side to have the same amount chlorine and to do this multiply KCl by 2. Fluorine however, has 2 atoms on the reactant side and 1 atom on the product side. to fix this multiply KF by 2. <span>Therefore the balanced reaction is: 2KCl+F₂→2KF+Cl₂
</span>notice how both sides of the reaction have equal numbers of each atom.
Mg+HCl→MgCl₂+H₂
the above reaction has 2 atoms of H on the products side and only 1 atom of H on the reactants side. That means you have to multiply HCl by 2. Now you have the equation Mg+2HCl→MgCl₂+H₂. As you can see now we have equal numbers of all the atoms on both sides which means that that is the balanced equation.
I hope this helps. Let me know if you have any further questions or need anything to be clarified.
You need to use the Ka for the acetic acid and the equilibrium equation.
Ka = 1.85 * 10^ -5
Equilibrium reaction: CH3COOH (aq) ---> CH3COO(-) + H(+)
Ka = [CH3COO-][H+] / [CH3COOH]
Molar concentrations at equilibrium
CH3COOH CH3COO- H+
0.50 - x x x
Ka = x*x / (0.50 - x) = x^2 / (0.50 - x)
Given that Ka is << 1 => 0.50 >> x and 0.50 - x ≈ 0.50
=> Ka ≈ x^2 / 0.50
=> x^2 ≈ 0.50 * Ka = 0.50 * 1.85 * 10^ -5 = 0.925 * 10^ - 5 = 9.25 * 10 ^ - 6
=> x = √ [9.25 * 10^ -6] = 3.04 * 10^ -3 ≈ 0.0030
pH = - log [H+] = - log (x) = - log (0.0030) = 2.5
Answer: 2.5
