Explanation:
Because the solution only contains Na+ and Cl− ions, and water, and not the metal Na(s) . You cannot evaporate the water from the solution and hope to obtain anything but NaCl(s) .
.
Na(s) has an electron configuration of 1s^2 2s^2 2p^6 3s^1 , but Na+(aq) has an electron configuration of 1s^2 2s^2 2p^6 . That means they are not the same element, and thus, there is no straightforward way of extracting Na(s) from a NaCl (aq) solution
Answer: pH of HCl =5, HNO3 = 1,
NaOH = 9, KOH = 12
Explanation:
pH = -log [H+ ]
1. 1.0 x 10^-5 M HCl
pH = - log (1.0 x 10^-5)
= 5 - log 1 = 5
2. 0.1 M HNO3
pH = - log (1.0 x 10 ^ -1)
pH = 1 - log 1 = 1
3. 1.0 x 10^-5 NaOH
pOH = - log (1.0 x 10^-5)
pOH = 5 - log 1 = 5
pH + pOH = 14
Therefore , pH = 14 - 5 = 9
4. 0.01 M KOH
pOH = - log ( 1.0 x 10^ -2)
= 2 - log 1 = 2
pH + pOH = 14
Therefore, pH = 14 - 2 = 12
Answer:
The correct option is: <u>B. 366 torr</u>
Explanation:
Given: <u>On the ground</u>- Initial Volume: V₁ = 8.00 m³, Initial Atmospheric Pressure: P₁= 768 torr;
<u>At 4200 m height</u>- Final Volume: V₂ = 16.80 m³, Final Atmospheric Pressure: P₂ = ?
Amount of gas: n, and Temperature: T = constant
<u>According to the Boyle's Law</u>, for a given amount of gas at constant temperature: P₁ V₁ = P₂ V₂
⇒ P₂ = P₁ V₁ ÷ V₂
⇒ P₂ = [(768 torr) × (8.00 m³)] ÷ (16.80 m³)
⇒ P₂ = 365.71 torr ≈ 366 torr
<u>Therefore, the final air pressure at 4200 m height: P₂ = 366 torr.</u>
Answer:
I. The balloon has a volume of 22.4L
III. The balloon contains 6.022x10^23 molecules.
Explanation:
At stp, it has been proven that 1mole of a gas occupy 22.4L.
Therefore, option (i) is correct.
The molar mass N2 = 14.01 x 2 = 28.02g/mol
Number of mole of N2 = 1 mole
Mass of N2 =..?
Mass = mole x molar Mass
Mass of N2 = 1 x 28.02 = 28.02g.
The mass content of the balloon is 28.02g, therefore, option (ii) is wrong.
From Avogadro's hypothesis, we understood that 1 mole of any substance contains 6.02x10^23 molecules. This implies that 1 mole of N2 also contains 6.02x10^23 molecules
Therefore, option (iii) is correct.
The correct options to the question are:
Option i and option iii
