Answer:
1.41 × 10⁻¹⁰ M
Explanation:
We have a solution with a pH of 9.85 at 25 °C. We can calculate the concentration of H⁺ using the following expression.
pH = -log [H⁺]
[H⁺] = antilog -pH
[H⁺] = antilog -9.85
[H⁺] = 1.41 × 10⁻¹⁰ M
H⁺ is usually associated with water molecules forming hydronium ions.
H⁺ + H₂O → H₃O⁺
Then, the concentration of H₃O⁺ ions is 1.41 × 10⁻¹⁰ M.
The percentage composition of CF4 is %C = 13.64% and %F = 86.36%
The solution are as follows:
Molar mass of CF4 = 88
<span>molar mass of C = 12 </span>
<span>molar mass of F = 4x19 = 76 </span>
<span>% C = 12/88 x 100 = 13.64% </span>
<span>% F = 76/88 x 100 = 86.36%</span>
Answer:
The fraction of water body necessary to keep the temperature constant is 0,0051.
Explanation:
Heat:
Q= heat (unknown)
m= mass (unknown)
Ce= especific heat (1 cal/g*°C)
ΔT= variation of temperature (2.75 °C)
Latent heat:
ΔE= latent heat
m= mass (unknown)
∝= mass fraction (unknown)
ΔHvap= enthalpy of vaporization (539.4 cal/g)
Since Q and E are equal, we can match both equations:
Mass fraction is:
∝=0,0051
Oh my i really hope no one from my school sees my comments
