Advertisements
Advertisements
प्रश्न
Answer in brief.
How much heat is evolved when 12 g of CO reacts with NO2? The reaction is:
4CO(g) 2NO2(g) → 4CO2(g) + N2(g), ΔrH° = - 1200 kJ
Advertisements
उत्तर
Given: ΔrH° = - 1200 kJ, Mass of CO = 12 g
To find: Heat evolved when 12g of CO reacts with NO2
Calculation:
According to the given reaction, 1200 kJ of heat is evolved when 4 moles of CO react with NO2. So heat evolved per mole is `(1200 "kJ")/(4 "mol")` = 300 kJ mol-1
Molar mass of CO = 12 + 16 = 28 g mol–1
Number of moles of CO = `"Mass of CO"/"Molar mass of CO" = (12 "g")/(28 "g mol"^-1)`= 0.4286 mol
So, heat evolved when 0.4286 moles of CO reacts
= 0.4286 mol × 300 kJ mol-1 = 128.58 kJ
The heat evolved when 12 g of CO reacts with NO2 is 128.58 kJ.
APPEARS IN
संबंधित प्रश्न
Select the most appropriate option.
Which of the following reactions is exothermic?
Answer in brief.
How will you calculate reaction enthalpy from data on bond enthalpies?
Calculate the total heat required
a) to melt 180 g of ice at 0 °C
b) heat it to 100 °C and then
c) vapourise it at that temperature.
[Given: ΔfusH° (ice) = 6.01 kJ mol-1 at 0 °C, ΔvapH° (H2O) = 40.7 kJ mol-1 at 100 °C, Specific heat of water is 4.18 J g-1 K-1]
The enthalpy change for the reaction, \[\ce{C2H4_{(g)} + H2_{(g)} -> C2H6_{(g)}}\] is −620 J when 100 mL of ethylene and 100 ml of \[\ce{H2}\] react at 1 bar pressure. Calculate the pressure volume type of work and ΔU for the reaction.
Calculate enthalpy of formation of HCl if bond enthalpies of H2, Cl2 and HCl are 434 kJ mol-1, 242 kJ mol–1 and 431 kJ mol–1 respectively.
The enthalpy change of the following reaction:
\[\ce{CH_{4(g)} + Cl_{2(g)} -> CH3Cl_{(g)} + HCl_{(g)}ΔH^0 = –104 kJ}\]
Calculate C – Cl bond enthalpy. The bond enthalpies are:
| Bond | C − H | Cl − Cl | H − Cl |
| ∆H°/kJ mol−1 | 414 | 243 | 431 |
Write an application of Hess’s law.
Classify the following into intensive and extensive properties.
Pressure, volume, mass, temperature.
When 2 moles of C2H6(g) are completely burnt, 3129 kJ of heat is liberated. If ∆Hf for CO2(g) and H2O(l) are −395 and −286 kJ per mole respectively, the heat combustion of C2H6(g) is ____________.
A compound that has a high negative heat of formation is normally ____________.
The volume of oxygen required for complete combustion of 0.25 mole of methane at STP is ______.
When 6.0 g of graphite reacts with dihydrogen to give methane gas, 37.4 kJ of heat is liberated. What is standard enthalpy of formation of CH4 (g)?
Daily requirement of energy of a person is 'x' kJ. If heat of combustion of food material (Molecular mass = 100 g) is 'y' kJ, his daily consumption of the food in gram would be ____________.
The enthalpy change accompanying a reaction in which 1 mole of the substance in the standard state reacts completely with oxygen or is completely burnt is called as ____________.
Which among the following salts, solubility decreases with increase in temperature?
The heat evolved in the combustion of benzene is given by
\[\ce{C6H6 + 7 1/2O2 -> 6CO2_{(g)} + 3H2O_{(l)}}\]; ΔH = −3264.6 kJ
Which of the following quantities of heat energy will be evolved when 39 g C6H6 are burnt?
Which of the following compounds is Not present in its standard state at 25°C and 1 atmosphere pressure?
Given the reaction,
\[\ce{CH2O_{(g)} + O2_{(g)} -> CO2_{(g)} + H2O_{(g)}}\] ΔH = −527 kJ
How much heat will be evolved in the formation of 60 g of CO2?
Identify the invalid equation.
What is the amount of water formed by the combustion of 1.6 g methane?
How many moles of helium gas occupies 22.4 Lat 0°c and at 1 atmospheric pressure?
When the enthalpy of combustion of carbon to carbon dioxide is - 360 kJ mol-1, then the enthalpy change for the formation of 18 g of CO2 from carbon and dioxygen at the same temperature in kJ will be ______.
The enthalpy change that accompanies a reaction in which 1 mole of its standard state is formed from its elements in their standard states
Define and explain the term, enthalpy of reaction.
Calculate the standard enthalpy of the reaction, \[\ce{SiO2_{(s)} + 3C_{(graphite)} -> SiC_{(s)} + 2CO_{(g)}}\] from the following reactions:
- \[\ce{Si_{(s)} + O2_{(g)} -> SiO2_{(s)}}\], ΔrH0 = −911 kJ
- \[\ce{2C_{(graphite)} + O2_{(g)} -> 2CO_{(g)}}\], ΔrH0 = −221 kJ
- \[\ce{Si_{(s)} + C_{(graphite)} -> SiC_{(s)}}\], ΔrH0 = −65.3 kJ
For the reaction, H2 + I2 ⇌ 2HI; ΔH = 12.4 kcal. The heat of formation of HI, ΔHf = ______.
Calculate heat evolved for combustion of 13 gm of acetylene (C2H2).
Given: \[\ce{C2H2_{(g)} + 5/2O_{2(g)}-> 2CO_{2(g)} + H2O_{(l)} \Delta_{(c)}H^{0} = - 1300 kJ}\]
