It's "C" a sample of dust particles at 0 Pascals
Answer:
-5.51 kJ/mol
Explanation:
Step 1: Calculate the heat required to heat the water.
We use the following expression.

where,
- c: specific heat capacity
- m: mass
- ΔT: change in the temperature
The average density of water is 1 g/mL, so 75.0 mL ≅ 75.0 g.

Step 2: Calculate the heat released by the methane
According to the law of conservation of energy, the sum of the heat released by the combustion of methane (Qc) and the heat absorbed by the water (Qw) is zero
Qc + Qw = 0
Qc = -Qw = -22.0 kJ
Step 3: Calculate the molar heat of combustion of methane.
The molar mass of methane is 16.04 g/mol. We use this data to find the molar heat of combustion of methane, considering that 22.0 kJ are released by the combustion of 64.00 g of methane.

Answer: 2m/s^2
Explanation:
Velocity of skateboard = 20.0 m/s.
Time taken = Ten seconds (10 s)
Acceleration = ?
Recall that acceleration is the change in velocity of a body per unit time.
i.e Acceleration = (velocity / Time)
Acceleration = 20.0m/s ➗ 10 s
Acceleration = 2m/s^2
Thus, Jeffrey acceleration was 2m/s^2
Answer: Option (c) is the correct answer.
Explanation:
When a weak acid reacts with a strong base then it results into the formation of a basic solution. Hence, the resulting solution will always have a pH greater than 7.
Since, at the equivalence point number of hydrogen ions become equal to the hydroxide ions. Therefore, pH of solution will be about 7.
So at the equivalence point, the weak acid will get neutralized due to the addition of strong base. Therefore, it will lead to the formation of conjugate base.
As a result, the solution will become slightly basic in nature.
Thus, we can conclude that at the equivalence point, the acid has all been converted into its conjugate base, resulting in a weakly acidic solution because at the equivalence point, the acid has all been converted into its conjugate base, resulting in a weakly basic solution.