Answer:
7.07
Explanation:
HA = weak acid = 0.053
A+ = conjugate base = 0.045
Ka = 7.2x10^-8
Ka = [H+][A-]/HA
7 2x10^-8 = [H+][0.045]/0.053
[H+] = 7.2x10^-8 x 0.053/0.045
= 8.48x10^-8
PH = -log[H+]
= -log[8.48x10^-8]
PH = -[login.48 + log10^-8]
PH = -0.928 - (-8)log10
= 7.07
Answer:
T = 246 K
Explanation:
Given that,
Number of moles, n = 0.750 mol
The volume of the cylinder, V = 6850 mL = 6.85 L
Pressure of the gas, P = 2.21 atm
We need to find the temperature of the gas stored in the cylinder. We know that,
PV= nRT
Where
R is gas constant
T is temperature
So,
or
T = 246 K
So, the temperature of the gas is equal to 246 K.
Using PV = nRT, we can calculate the moles of the sample.
874 mmHg = 116,524 Pa
n = PV/RT
n = 116,524 x 294 x 10⁻⁶ / 8.314 x (140 + 273)
n = 9.98 x 10⁻³ mol
moles = mass / Mr
Mr = 0.271/9.98 x 10⁻³
Mr = 27.2
Mass of empirical formula = 14
Repeat units = 27.2 / 14 ≈ 2
Formula of substance:
C₂H₄
Combustion equation:
C₂H₄ + 3O₂ → 2CO₂ + 2H₂O
1 mole produces 2 moles of CO₂, so 3 moles will produce 6 moles CO₂
Answer:
lead ii nitrate is the answer
Voulme 1= 950 mL
Volume 2= ?
Temperature 1 = 25 C
Temperature 2 = 50 C
Convert your temperature to Kelvin
C+273=K
Temperature 1 = 25 C + 273 = 298 K
Temperature 2 = 50 C + 273 = 323 K
Plug in to the Formula
950 mL/298 K = ? / 323 K
Rearrange the formula to make one to solve for what is missing.
To get 323 K out of the denominator multiply by it.
Making it
950 mL x 323 K / 298 K = ?
Plug it in
950 mL x 323 K / 298 K = 1027.9 mL
