Question

Какое количество теплоты выделится при полном сгорании 20г водорода

Answer 1

Решение:

Q=ʎm

 m=20г=0.02кг

ʎ=120х106Дж/кг-удельная теплоемкость водорода

Q(количество теплоты)=0.02х120х106=2.4х106Дж/кг

Answer 2

Calculating the Heat Released from the Complete Combustion of 20g of Hydrogen

To calculate the amount of heat released from the complete combustion of 20g of hydrogen, we can use the formula:

Q = m * ΔH

Where: - Q = heat released - m = mass of the substance (in grams) - ΔH = enthalpy change for the reaction

The enthalpy change for the combustion of hydrogen is -286 kJ/mol.

Using this information, we can calculate the heat released.

Calculation

The molar mass of hydrogen (H2) is 2 g/mol.

The number of moles of hydrogen in 20g can be calculated as: moles = mass / molar mass moles = 20g / 2 g/mol moles = 10 mol

Now, we can calculate the heat released using the enthalpy change: Q = moles * ΔH Q = 10 mol * (-286 kJ/mol) Q = -2860 kJ

Therefore, the amount of heat released from the complete combustion of 20g of hydrogen is 2860 kJ.