Let's assume that CH₄ has ideal gas behavior.
Then we can use ideal gas formula,
PV = nRT
Where, P is the pressure of the gas (Pa), V is the volume of the gas (m³), n is the number of moles of gas (mol), R is the universal gas constant ( 8.314 J mol⁻¹ K⁻¹) and T is temperature in Kelvin.
P = 1 atm = 101325 Pa
V = 1.50 L = 1.50 x 10⁻³ m³
n = ?
R = 8.314 J mol⁻¹ K⁻¹
T = 0 °C = 273 K
By substitution,
101325 Pa x 1.50 x 10⁻³ m³ = n x 8.314 J mol⁻¹ K⁻¹ x 273 K
n = 0.0669 mol
Hence, moles of CH₄ = 0.0669 mol
Moles = mass / molar mass
Molar mass of CH₄ = 16 g mol⁻¹
Mass of CH₄ = moles x molar mass
= 0.0669 mol x 16 g mol⁻¹
= 1.0704 g
Hence, mass of CH₄ in 1.50 L at STP is 1.0704 g
Photosynthesis Is a Reaction To Make Food.Aerobic Cellular Respiration Is a Reaction With Oxygen
Anaerobic Respiration - Everyday Chemical Reactions.Combustion Is a Type of Chemical Reaction
Rust Is a Common Chemical Reaction
Mixing Chemicals Causes Chemical Reactions.
it happens all the time every day in life:)
Answer:
People, especially kids, tend to think that when water evaporates it just disappears, or turns into the air. But we know based on the law of conservation of mass that any time water changes state it keeps the same mass!
Similarly, when water vapor turns to water droplets, when it goes from its gas to its liquid state, it still has the same mass. It's just in a different phase. This is a perfect example of conservation in mass!
Strategy: with the volume, pressure and temperature you can find the number of moles.
With the number of moles and the mass in grams you can find the molar mass of the gas, and with the molar mass you can figure out the gas.
1) pV = nRT => n = pV / RT
R = 0.082 atm*liter / mol*K
T = 62 + 273.15 = 335.15 K
p = 1.98 atm
V = 0.752 liter
n = (1.98 atm * 0.752 liter) / [0.082 atm* liter / (mol * K) * 335.15K] = 0.05418 mol
2) molar mass = mass / n = 2.49 g / 0.05418 mol = 45.96 g/mol ≈ 46.0 g/mol
So, now you must compare this molar mass with the molar masses of the list of choices.
For example, for NO2 the molar mass is 14 g/mol + 2 * 16 g/mol = 14 g/mol + 32 g/mol = 46 g / mol.
Given that NO2 is in the list of choices, you can conclude that the gas is NO2.