POH value was calculated by the negative logarithm of hydroxide ion concentration.
To know the hydrogen ion concentration, we need to know the pH value, that can be found out if pOH is known
pH + pOH = 14
pH = 14 - pOH
pH = 10.65
once the pH is known we have to find the antilog.
[H⁺] = antilog (-pH)
antilog can be found by
[H⁺] = 10^(-10.65)
[H⁺] = 2.2 x 10⁻¹¹ M
At room temperature the air is Gas
Answer:
w = -531 kJ
1. Work was done by the system.
Explanation:
Step 1: Given data
- Heat gained by the system (q): 687 kJ (By convention, when the system absorbs heat, q > 0).
- Change in the internal energy of the system (ΔU°): 156 kJ
Step 2: Calculate the work done (w)
We will use the following expression.
ΔU° = q + w
w = ΔU° - q
w = 156 kJ - 687 kJ
w = -531 kJ
By convention, when w < 0, work is done by the system on the surroundings.
Answer:
0.0845 M
Explanation:
First we <u>convert 4.27 grams of potassium iodide into moles</u>, using its <em>molar mass</em>:
- Molar Mass of KI = 166 g/mol
- 4.27 g ÷ 166 g/mol = 0.0257 mol
Now we <u>calculate the molarity of the solution</u>, using <em>the number of moles and the given volume</em>:
- Molarity = moles / liters
- Molarity = 0.0257 mol / 0.304 L = 0.0845 M