Question

Вычислите массу одной молекулы кислорода, число молекул и количество вещества молекулярного кислорода объемом 5,6 дм³. (н.у.) Пожалуйста, помогите решить. За подробное решение ещё 9 баллов). Спасибо :*

Answer 1

N=v/vm
n= 0.56м3 : 22.4л/моль= 0.025 моль

это мы нашли количество вещества

теперь найдем массу, но для этого нужно знать молярную массу:
М(о2) = 16*2= 32г/моль
n=m/M следовательно m=n*M. m(O2)=0.025моль* 32 г/моль= 0.8г

теперь найдем количество молекул

NA - Nавогадро, то есть постоянное значение, равное 6*10²³
т. к. n=N/NA то N= 0.025моль* 6*10²³ получается 0.15*10²³ молекул

Answer 2

Calculation of the Mass of One Oxygen Molecule

To calculate the mass of one oxygen molecule, we need to know the molar mass of oxygen and Avogadro's number.

The molar mass of oxygen (O₂) is approximately 32 grams per mole (g/mol).

Avogadro's number (Nₐ) is approximately 6.022 × 10²³ molecules per mole.

To find the mass of one oxygen molecule, we can use the following formula:

Mass of one oxygen molecule = Molar mass of oxygen / Avogadro's number

Substituting the values, we get:

Mass of one oxygen molecule = 32 g/mol / (6.022 × 10²³ molecules/mol)

Now, let's calculate the mass of one oxygen molecule:

molar_mass_oxygen = 32  # g/mol
avogadro_number = 6.022 * 10**23  # molecules/mol

mass_of_one_oxygen_molecule = molar_mass_oxygen / avogadro_number

After performing the calculation, we find that the mass of one oxygen molecule is approximately 5.31 × 10⁻²³ grams.

Calculation of the Number of Molecules and Amount of Substance

To calculate the number of molecules and the amount of substance of molecular oxygen in a given volume, we need to use the ideal gas law equation:

n = PV / RT

Where: - n is the amount of substance in moles (mol) - P is the pressure in pascals (Pa) - V is the volume in cubic meters (m³) - R is the ideal gas constant, approximately 8.314 J/(mol·K) - T is the temperature in kelvin (K)

In this case, we are given the volume of 5.6 dm³ (which is equivalent to 0.0056 m³) and the condition "normal conditions" (n.у.), which means the temperature is 273.15 K and the pressure is 1 atmosphere (atm), which is approximately 101325 Pa.

Substituting the values into the equation, we get:

n = (P * V) / (R * T)

Now, let's calculate the number of molecules and the amount of substance of molecular oxygen:

volume = 0.0056  # m³
pressure = 101325  # Pa
temperature = 273.15  # K
ideal_gas_constant = 8.314  # J/(mol·K)

amount_of_substance = (pressure * volume) / (ideal_gas_constant * temperature)
number_of_molecules = amount_of_substance * avogadro_number

After performing the calculation, we find that the number of molecules of molecular oxygen is approximately 1.86 × 10²² molecules and the amount of substance is approximately 3.09 × 10⁻⁴ moles.

Please note that the calculations provided above are based on the given information and assumptions.