Question

Масса неизвестного простого вещества (состоящего из двухатомных молекул) количеством 0, 2 моль составляет 14, 2г. 1-Определите, что это за вещество. Напишите символ элемента 2-Вычислите, какой объем (л) занимает данное количество вещества (ответ запишите с точностью до сотых).

Answer 1

N=0.2 (моль)
m=14.2 (г)

M=m/n=14.2/0.2=71 (г/моль)
Вещество:   Cl2

V=Vm*n, где Vm - объем газа при н.у. = 22.4 (л/моль)
V=22.4*0.2=4.48 (л)

Answer 2

Identification of the Substance

The unknown substance consists of two-atom molecules and has a mass of 14.2 grams for a quantity of 0.2 moles. To determine the identity of the substance, we can calculate its molar mass by dividing the mass by the number of moles:

Molar mass = Mass / Moles

Molar mass = 14.2 g / 0.2 mol

Molar mass = 71 g/mol

Therefore, the molar mass of the unknown substance is 71 g/mol.

Unfortunately, the search results did not provide any specific information about the substance. However, we can use the molar mass to make an educated guess based on the periodic table. The molar mass of 71 g/mol is close to the molar mass of bromine (Br), which is approximately 79.9 g/mol. However, without further information, we cannot definitively determine the identity of the substance.

Calculation of Volume

To calculate the volume occupied by the given quantity of the substance, we need to use the ideal gas law equation:

PV = nRT

Where: - P is the pressure (which is not given in the question) - V is the volume - n is the number of moles (0.2 mol in this case) - R is the ideal gas constant (8.314 J/(mol·K)) - T is the temperature (which is not given in the question)

Since the pressure and temperature are not provided, we cannot calculate the exact volume. However, we can use the ideal gas law to calculate the volume if we assume standard temperature and pressure (STP), which are defined as 0 degrees Celsius (273.15 Kelvin) and 1 atmosphere (101.325 kilopascals) respectively.

Using STP, the ideal gas law equation simplifies to:

V = nRT / P

Substituting the given values:

V = (0.2 mol) * (8.314 J/(mol·K)) * (273.15 K) / (101.325 kPa)

Converting kilopascals to pascals:

V = (0.2 mol) * (8.314 J/(mol·K)) * (273.15 K) / (101325 Pa)

Calculating the volume:

V ≈ 4.48 liters

Therefore, the approximate volume occupied by the given quantity of the substance is 4.48 liters.

Please note that the calculated volume assumes standard temperature and pressure (STP) and may not be accurate if the actual conditions differ from STP.