Answer:
a.
Explanation:
At 28 degrees highest line is CaCl2. Answer a.
The answer is sodium chloride.
Explanation:
Sodium chloride refers to table salt, and is the most abundant of salts found in seawater.
Answer:
pH = 6.8124
Explanation:
We know pH decreases with increase in temperature.
At room temperature i.e. 25⁰c pH of pure water is equal to 7
We know
Kw = [H⁺][OH⁻]...............(1)
where Kw = water dissociation constant
At equilibrium [H⁺] = [OH⁻]
So at 37⁰c i.e body temperature Kw = 2.4 × 10⁻¹⁴
From equation (1)
[H⁺]² = 2.4 × 10⁻¹⁴
[H⁺] = √2.4 × 10⁻¹⁴
[H⁺] = 1.54 × 10⁻⁷
pH = - log[H⁺]
= - log{1.54 × 10⁻⁷}
= 6.812
Answer:
–500KJ
Explanation:
Data obtained from the question include the following:
Heat of reactant (Hr) = 800KJ
Heat of product (Hp) = 300KJ
Enthalphy change (ΔH) =..?
The enthalphy change is simply defined as the difference between the heat of product and the heat of reactant i.e
Enthalphy change = Heat of product – Heat of reactant
ΔH = Hp – Hr
With the above formula, we can easily calculate the enthalphy change as follow
ΔH = Hp – Hr
ΔH = 300 – 800
ΔH = –500KJ.
Therefore, the overall energy change for the reaction between hydrogen and oxygen shown in the diagram above is –500KJ
Answer:
13.20
Explanation:
Step 1: Calculate the moles of Ba(OH)₂
The molar mass of Ba(OH)₂ is 171.34 g/mol.
0.797 g × 1 mol/171.34 g = 4.65 × 10⁻³ mol
Step 2: Calculate the molar concentration of Ba(OH)₂
Molarity is equal to the moles of solute divided by the liters of solution.
[Ba(OH)₂] = 4.65 × 10⁻³ mol/60 × 10⁻³ L = 0.078 M
Step 3: Calculate [OH⁻]
Ba(OH)₂ is a strong base according to the following equation.
Ba(OH)₂ ⇒ Ba²⁺ + 2 OH⁻
The concentration of OH⁻ is 2/1 × 0.078 M = 0.16 M
Step 4: Calculate the pOH
pOH = -log OH⁻ = -log 0.16 = 0.80
Step 5: Calculate the pH
We will use the following expression.
pH + pOH = 14
pH = 14 - 0.80 = 13.20
