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:
T₂ = 669.2 K
Explanation:
Given data:
Initial pressure = 660 torr
Initial temperature = 26 °C (26 +273 = 299 K)
Final volume = 280 mL ( 280/1000 = 0.28 L)
Final pressure = 940.0 torr
Final volume = 0.44 L
Final temperature = ?
Formula:
P₁V₁/T₁ = P₂V₂/T₂
P₁ = Initial pressure
V₁ = Initial volume
T₁ = Initial temperature
P₂ = Final pressure
V₂ = Final volume
T₂ = Final temperature
Solution:
P₁V₁/T₁ = P₂V₂/T₂
T₂ = P₂V₂ T₁ /P₁V₁
T₂ = 940 torr × 0.44 L × 299 K / 660 torr × 0.28 L
T₂ = 123666. 4 torr. L. K / 184.8 torr. L
T₂ = 669.2 K
The force on the wall is actually the pressure exerted by gas molecules
Higher the pressure more the force exerted on the walls of container
The pressure depends upon the number of molecules of a gas
In a mixture of gas the pressure depends upon the mole fraction of the gas
As given the mole fraction of He is more than that of H2 therefore He will exert more pressure on the wall
The ratio of impact will be
H2 / He = 2/3 / 1/3 = 2: 1
Total mass of CaCO3 = 40 amu of Ca + 12amu of C + 16×3 amu of oxygen = 100amu of CaCO3
i.e 100 tonnes of CaCO3 .
mass of CO2 = 12amu of C + 2× 16amu of O = 44 amu of CO2
mass % of CO2 in CaCO3 = (44/100)×100 =44%
i.e
44% of 100 tonnes is CO2.
=44 tonnes of CO2.
therefore, 44% of CO2 is present in CaCO3.
Anna lives in a city that is part of the tropical climate types. It has a constantly warm weather, and thus higher humidity, and according to the annual rainfall, it is most probably a rainfall that appears seasonally, not throughout the whole year.
Tim, on the other hand, lives in a city that is part of the dry climate types. It is most probably a place that is deep into the mainland, like the cold deserts of Central Asia, where the temperatures in the summer are high, and in winter are very low. Because of the distance from the sea, the rainfall doesn't reach this places, so they are very dry, and only have symbolic amount of annual rainfall.
