Answer:
10.10
Explanation:
Step 1: Write the basic dissociation reaction for pyridine
C₅H₅N(aq) + H₂O(l) ⇌ C₅H₅NH⁺(aq) + OH⁻(aq) Kb = 1.9 × 10⁻⁹
Step 2: Calculate [OH⁻]
For a weak base, we will use the following expression.
[OH⁻] = √(Cb × Kb) = √(9.2 × 1.9 × 10⁻⁹) = 1.3 × 10⁻⁴ M
Step 3: Calculate pOH
We will use the definition of pOH.
pOH = -log [OH⁻] = -log 1.3 × 10⁻⁴ = 3.9
Step 4: Calculate pH
We will use the following expression.
pH = 14 - pOH = 14 - 3.9 = 10.10
Answer:
Rust is a chemical reaction (oxidation) of iron that occurs over a period of time as the bare metal surface comes in contact with oxygen present in the air or water. Rust "eats" away the metal, rendering it weak and fragile. ... Avoid contact with water or moisture.
Answer:
B
Explanation:
Hydrogen is synthesized to water by adding Oxygen.
Hydrogen is oxidised to water by combustion ( burning in presence of oxygen).
Answer: Salt and Water
Explanation:
An Arrhenius acid (HCl) can best be defined as any substance that when added to water increases the concentration of H+ ions.
While an Arrhenius base (KOH) is any substance that when added to water increases the concentration of OH- ions.
When an Arrhenius acid such as HCl reacts with an Arrhenius base such as KOH, the end products will be salt and water, in a process called Neutralization Reaction.
HCl (aq) + KOH (aq) -------> KCl (aq) + H2O (l)
Answer:
The equivalent weight of M is approximately 31.8 g
The equivalent weight of N is approximately 27.98 g
Explanation:
The given parameters are;
The percentage of the the metal M in in the chloride = 47.25%
Where by the chemical formula for the metal chloride is MClₓ, we have;
47.25% of the mass of MClₓ = Mass of M = W
Therefore, we have;
0.4725 × (W + 35.5·x) = W
0.4725·W + 0.4725×35.5×x = W
W - 0.4725·W = 16.77·x
0.5275·W = 16.77·x
W/x = 16.77/0.5275 = 31.799 = The equivalent weight of M
The equivalent weight of M = 31.799 ≈ 31.8 g
Given that 1 gram of M is displaced by 0.88 gram of N, then the equivalent weight of N that will displace 31.799 = 0.88 × 31.799 ≈ 27.98 g
The equivalent weight of N = 27.98 g.
