The answer is D hope this helps
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
<h3><u>Answer;</u></h3>
Acids; HCl and HC5H5N+
Bases; C5H5N and Cl-
<h3><u>Explanation;</u></h3>
- According to Bronsted-Lowry Theory an acid is a proton or hydrogen ion donor while a base is a proton or a hydrogen ion acceptor.
- In this case,<u> both HCl and HC5H5N+ are acids</u> as <u>they are donors of hydrogen ions</u>. HCl is an acid to the forward reaction while HC5H5N+ is a acid to the reverse reaction.
- On the other hand, <u>C5H5N and Cl- are bases</u>, <u>they are acceptors of hydrogen ions</u>. Cl- is a base in the reverse reaction while C5H5N is a base in the forward reaction.
Well, first of all, the formula for finding potential energy is;
PE=mgh
Where; m is the mass
g is the gravitational force or acceleration due to gravity
h is the height.
Anyway, according to the question, the mass is 1kg, the acceleration due to gravity has a constant value of 10ms² . And the height is 3m. Now you just have to use all these in the formula. So;
mgh= 1 x 10 x 3. That will be 30. And the unit of potential energy is Joule. So the answer is 30 joules. Hope i helped. Have a nice day.