Answer:
H⁺(aq) + H₂O(l) ⇄ H₃O⁺(aq)
Explanation:
According to Brönsted-Lowry acid-base theory, an acid is a substance that donates H⁺. Let's consider the molecular equation showing that benzoic acid is a Brönsted-Lowry acid.
C₆H₅COOH(aq) + H₂O(l) ⇄ C₆H₅COO⁻(aq) + H₃O⁺(aq)
The complete ionic equation includes all the ions and molecular species.
C₆H₅COO⁻(aq) + H⁺(aq) + H₂O(l) ⇄ C₆H₅COO⁻(aq) + H₃O⁺(aq)
The net ionic equation includes only the ions that participate in the reaction and the molecular species.
H⁺(aq) + H₂O(l) ⇄ H₃O⁺(aq)
Answer:
1
Explanation:
There is only one calcium atom because the subscript 3 applies only to the oxygen. Outside of the parentheses, the subscript 2 only applies to the chlorate ion. Therefore, there is only one calcium atom because there are no coefficients and subscripts. (Also drawing it out will help)
Answer:
P2 = 352 mm Hg (rounded to three significant figures)
Explanation:
PV = nRT
where P is the pressure,
V is the volume,
n is the moles of gas,
R is the gas constant,
and T is the temperature.
We must relate this equation to a sample of gas at two different volumes however. Looking at the equation, we can relate the change in volume by:
P1V1 = P2V2
where P1 is the initial pressure,
V1 is the initial volume,
P2 is the final pressure,
and V2 is the final volume.
Looking at this relationship, pressure and volume have an indirect relationship; when one goes up, the other goes down. In that case, we can use this equation to solve for the new pressure.
P1V1 = P2V2
(759 mm Hg)(1.04 L) = P2(2.24 L)
P2 = 352 mm Hg (rounded to three significant figures)
M(NiS₂) = 11.2 g.
n(NiS₂) = m(NiS₂) ÷ M(NiS₂).
n(NiS₂) = 11.2 g ÷ 122.8 g/mol.
n(NiS₂) = 0.091 mol.
m(O₂) = 5.43 g.
n(O₂) = 5.43 g ÷ 32 g/mol.
n(O₂) = 0.17 mol; limiting reactant.
From chemical reaction: n(NiS₂) : n(O₂) = 2 : 5.
0.091 mol : n(O₂) = 2 : 5.
n(O₂) = 0.2275 mol, not enough.
n(NiO) = 4.89 g .
n(O₂) : n(NiS) = 5 : 2.
n(NiS) = 0.068 mol.
m(NiS) = 0.068 mol · 74.7 g/mol = 5.08 g.
percent yield = 4.89 g / 5.08 g · 100% = 96.2%.
