Answer:
The answer to your question is 0.005
Explanation:
Data
Volume of NaOH = 25 ml
[NaOH] = 0.2 M
moles of NaOH = ?
To solve this problem is not necessary to have the chemical reaction. Just use the formula of Molarity and solve it for moles.
Formula
Molarity = moles / volume
-Solve for moles
moles = Molarity x volume
-Convert volume to liters
1000 ml ---------------- 1 l
25 ml ---------------- x
x = (25 x 1) / 1000
x = 0.025 l
-Substitution
moles = 0.2 x 0.025
-Result
moles = 0.005
Answer:
Vapour pressure of a liquid varies with temperature
Explanation:
The vapour pressure of any liquid is directly proportional to the temperature of the liquid. This implies that, as the temperature of the liquid increases, the vapour pressure increases likewise and vice versa.
Since the vapour pressure of liquid varies with the temperature of the liquid, it is essential to know the water temperature in the experiment to determine the vapour pressure of water.
<u>Answer:</u> The volume of concentrated solution required is 9.95 mL
<u>Explanation:</u>
To calculate the pH of the solution, we use the equation:
![pH=-\log[H^+]](https://tex.z-dn.net/?f=pH%3D-%5Clog%5BH%5E%2B%5D)
We are given:
pH = 0.70
Putting values in above equation, we get:
![0.70=-\log[H^+]](https://tex.z-dn.net/?f=0.70%3D-%5Clog%5BH%5E%2B%5D)
![[H^+]=10^{-0.70}=0.199M](https://tex.z-dn.net/?f=%5BH%5E%2B%5D%3D10%5E%7B-0.70%7D%3D0.199M)
1 mole of nitric acid produces 1 mole of hydrogen ions and 1 mole of nitrate ions.
Molarity of nitric acid = 0.199 M
To calculate the volume of the concentrated solution, we use the equation:
where,
are the molarity and volume of the concentrated nitric acid solution
are the molarity and volume of diluted nitric acid solution
We are given:
Putting values in above equation, we get:
Hence, the volume of concentrated solution required is 9.95 mL
I think the answer is 101.2 L
There are 1.078 x 10²³ molecules
<h3>Further explanation</h3>
Given
4 dm³ = 4 L Nitrogen gas
Required
Number of molecules
Solution
Assumptions on STP (1 atm, 273 K), 1 mol gas = 22.4 L, so for 4 L :
mol = 4 : 22.4
mol = 0.179
1 mol = 6.02 x 10²³ particles(molecules, atoms)
For 0.179 :
= 0.179 x 6.02 x 10²³
= 1.078 x 10²³
