Question

Сколько теплоты выделится,если сгорит 100 л вещества CH4

Answer 1

11,2 дм3 = 11,2 л n(СН4) = 11,2/22.4 = 0.5 мольтак как метана вяли в два раза меньше, то и еплоты выделится в два раза меньше:804/2=402 кДж
Не уверена, что правильно, но надеюсь что правильно

Answer 2

Calculation of Heat Released from Burning 100 L of CH4

To calculate the amount of heat released when 100 L of CH4 (methane) burns, we need to consider the balanced chemical equation for the combustion of methane:

CH4 + 2O2 -> CO2 + 2H2O

From the balanced equation, we can see that 1 mole of methane (CH4) reacts with 2 moles of oxygen (O2) to produce 1 mole of carbon dioxide (CO2) and 2 moles of water (H2O).

To calculate the amount of heat released, we need to know the enthalpy change of the reaction, which is given by the standard enthalpy of combustion (ΔHc). The standard enthalpy of combustion is the heat released when one mole of a substance is completely burned in excess oxygen under standard conditions.

The standard enthalpy of combustion of methane (ΔHc) is approximately -890 kJ/mol.

To calculate the heat released when 100 L of CH4 burns, we need to convert the volume of CH4 to moles. The molar volume of any gas at standard temperature and pressure (STP) is 22.4 L/mol.

Therefore, the number of moles of CH4 in 100 L can be calculated as follows:

100 L CH4 * (1 mol CH4 / 22.4 L CH4) = 4.46 mol CH4

Now, we can calculate the heat released using the following equation:

Heat released = ΔHc * moles of CH4

Heat released = -890 kJ/mol * 4.46 mol CH4

Heat released = -3969.4 kJ

Therefore, if 100 L of CH4 burns, approximately 3969.4 kJ of heat will be released.

Please note that the negative sign indicates that the reaction is exothermic, meaning heat is released during the reaction.