Question

Решите плиз + запишите еще и ДАНО. 1)в пересчете на 1 кг массы человека для дыхания необходимо 0.385г кислородав час. Найдите массу воздуха, необходимую в сутки для дыхания человеку массой 50 кг. Подсчитайте сколько приблизительно нужно воздуха (кг) 2) в промышленности для получения тепла используют кокс. Какой объем воздуха необходим для сжигания 1 т кокса (углерода С) с содержанием 10% негорючих примесей? Объемная доля кислорода в воздухе 21%

Answer 1

Дано: m(1кг)-t(1ч) = 0.385г Найти: m(50кг)-t(24ч) =? Решение: Найдем массу кислорода которую потребляет человек массой 50кг за 1ч: m(50кг)-t(1ч) = 50*0.385=19.25г Т. к. в сутках 24 часа, находим массу кислорода , которую он потребляет за сутки: m(50кг)-t(24ч)=19.25*24=462г=0.462кг Ответ: 0.462кг. 2. Дано: m(C)=1000 кг w(примеси)=10% w (O2)=21% Найти: V (O2) -? Решение: С+О2=СО2 m(чистого С)=1000*0.9=900кг n(С)=n(O2)=900000/12=75000моль V=n*Vm*w - только в данном случае такая формула V(O2)=75000*22.4*0.21=352800л. Ответ:352800л

Answer 2

Calculation 1: Mass of Air Required for Breathing

To find the mass of air required for breathing in one day, we need to calculate the mass of oxygen required for breathing and then convert it to the mass of air.

Given: - Mass of oxygen required for breathing per hour = 0.385 g - Mass of a person = 50 kg

To find the mass of oxygen required for breathing in one day, we can multiply the mass required per hour by the number of hours in a day (24 hours):

Mass of oxygen required per day = 0.385 g/hour * 24 hours = 9.24 g/day

To convert the mass of oxygen to the mass of air, we need to consider the composition of air. Air is composed of approximately 21% oxygen and 79% nitrogen by volume. Since the mass of nitrogen is much greater than the mass of oxygen, we can assume that the mass of air is approximately equal to the mass of oxygen.

Therefore, the mass of air required for breathing in one day is approximately 9.24 g.

Calculation 2: Volume of Air Required for Burning Coke

To find the volume of air required for burning 1 ton (1000 kg) of coke with a carbon content of 10% and 21% oxygen in the air, we need to calculate the amount of oxygen required for complete combustion.

Given: - Mass of coke = 1 ton = 1000 kg - Carbon content in coke = 10% - Oxygen content in air = 21%

To calculate the amount of oxygen required for complete combustion, we can use the stoichiometry of the reaction:

C + O2 -> CO2

From the balanced equation, we can see that 1 mole of carbon reacts with 1 mole of oxygen to produce 1 mole of carbon dioxide. The molar mass of carbon is 12 g/mol, and the molar mass of oxygen is 32 g/mol.

First, let's calculate the moles of carbon in 1 ton of coke:

Moles of carbon = Mass of carbon / Molar mass of carbon = (10% * 1000 kg) / 12 g/mol = 83.33 mol

Since the stoichiometry of the reaction is 1:1, we need the same number of moles of oxygen as moles of carbon.

Moles of oxygen = Moles of carbon = 83.33 mol

To find the mass of oxygen required, we can multiply the moles of oxygen by the molar mass of oxygen:

Mass of oxygen = Moles of oxygen * Molar mass of oxygen = 83.33 mol * 32 g/mol = 2666.56 g

To convert the mass of oxygen to volume, we need to consider the volume percent of oxygen in air. Since the oxygen content in air is 21%, we can calculate the volume of air required using the following formula:

Volume of air = Mass of oxygen / (Density of air * Volume percent of oxygen in air)

The density of air is approximately 1.225 kg/m^3.

Volume of air = 2666.56 g / (1.225 kg/m^3 * 0.21) = 10218.54 m^3

Therefore, the volume of air required for burning 1 ton of coke is approximately 10218.54 m^3.

Please note that these calculations are approximate and may vary depending on the specific conditions and assumptions made.