Answer:
3.51
Explanation:
Before any sodium hydroxide has been added, the pH is that of the aqueous hydrofluoric acid solution.
HF is a weak acid that dissociates according to the following equation.
HF(aq) ⇄ H⁺(aq) + F⁻(aq) Ka = 6.76 × 10⁻⁴
We can find [H⁺] using the following expression.
[H⁺] = √(Ca × Ka)
where
Ca: concentration of the acid
Ka: acid dissociation constant
[H⁺] = √(Ca × Ka)
[H⁺] = √(0.458 × 6.76 × 10⁻⁴)
[H⁺] = 3.10 × 10⁻⁴ M
The pH is:
pH = -log [H⁺]
pH = -log 3.10 × 10⁻⁴ = 3.51
Answer:
i am not 100% shure but the wind speed has little to effect it so a and b are not the answer so i think the answer is D
Explanation:if i got this wrong im sorry it has bin a wile since i answered a question like this.
Answer:
The volume of the gas sample at standard pressure is <u>819.5ml</u>
Explanation:
Solution Given:
let volume be V and temperature be T and pressure be P.
1 torr= 1 mmhg
42.2 torr=42.2 mmhg
so,
Now
firstly we need to find the pressure due to gas along by subtracting the vapor pressure of water.
=735-42.2=692.8 mmhg
Now
By using combined gas law equation:
Here 
are standard pressure and temperature respectively.
we have
Substituting value, we get
Density increases with the temperature, true.
Radioactivity in our world <span>b. is as old as the universe.
</span><span>Radioactive atom spontaneously emits energetic particles or waves, while decays on lighter nuclei (atoms with smaller atomic mass). Radioactivity is used to calculate how old is Earth and living things, for that purpose isotope of carbon is used.</span>
