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Noble gases have high positive values of electron gain enthalpy
Standard enthalpy of vapourisation DvapHQ for water at 100° C is 40.66 kJmol–1. The internal energy of vapourisation of water at 100°C (in kJmol–1) is ?
what is the difference between Qc and kc.
calculate the standard enthalpy of formation of ethene (C2H4)from the following equation-
C2H4(g) + 3O2(g)-----》 2CO2 +2H2O enthalpy of formatiom of reaction is -1323 kJ/m
Enthalpy of formation of CO2,H2O and O2 are -393.5 ,-249,0 respectively
The work done in an open vessel at 300 K, when 112 g iron reacts with dil HCl to give FeCl2 is?
Ans 1.2 kcal
please explain cp-cv=R briefly
calculate the enthalpy of formation of methane
C +O2 --CO2 deltaH = -393.7 KJ/MOL
H2+1/2 O2 ---H2O H= -285.8 KJ/MOL
CH4 +2O2 ---CO2+2H2O H = -890.4 KJ/MOL
Derive Gibbs Energy change and non mechanical work.
Why does a liquid boils at a lower temperature at the top of a mountain than at sea level?
derive the relationship between delta H and delta U for an ideal gas .explain each term involved in the equation.
what is the value of (delta) ng for the following reaction :-
H2(g) + I2(g) -- 2HI(g)
Which of the following process when carried out at a constant pressure can have value of w to be positive ?
Sn + 2 F2 --------- Sn F4
PCl5-------- PCl3 + cl2
C+ O2-------CO2
CaCO3------------CaO + CO2
THE HEAT OF COMBUSTION OF METHANE AT CONSTANT VOLUME IS MEASURED IN A BOMB CALORIMETER AT 298K AND IS FOUND TO BE -885KJ/MOL. CALCULATE THE HEAT OF COMBUSTION AT COSTANT PRESSURE.
If enthalpy of a reaction CH2Cl2 (g) --- C (g) + 2H (g) + 2Cl (g) is 1482 kJ/mol and bond dissociation enthalpy of (C-H) bond is 415 kJ/mol than bond dissociation enthalpy of (C-Cl) bond is
A spherical balloon of 21 cm diameter is to be filled up with hydrogen at NTP from a cylinder containing the gas at 20 atm. at 27 degree celcius. If the cylinder can hold 2.82 litres of water, calculate the numbers of balloons that can be filled up ?
what is atomicity of gas?explain briefly
Find the difference between heats of reaction at constant pressure and constant volume for the following reaction at 25 C in kJ.2C6H6 + 15O2 ---------> 12CO2 + 6H2O.
why change in volume is area * displacement??
What do you mean by Cp and Cv. Derive the relation between Cp and Cv.
Why delta v is negative?
Derive Cp- Cv = R.
Predict the feasibility of a reaction when
(i) both delta H and delta S increases.
(ii)both delta H and delta S decreases.
(iii)delta H increases but delta S decreases.
(iv)delta H decreases but delta S increases.
calculate the enthalpy of the reaction of C2H4(g)+H2(g) give rise to C2H6(g)from the the following data??
pls fast urgent I want it within 2hrs????pls plsssssssss help
what is the use of stirrer in these calorimeters..
Calorific valueof ethane, in kJ/g if for the rxn
2C2H6 + 7O2--- 4CO2 + 6H2O + 745.6 kcal
Ans -52
How?
how to convert Ethyne to acetaldehyde ?
How Vf − Vi can be negative ? plz explain
If water vapour is assumed to be a perfect gas, molar enthalpy change for vapourisation of 1 mol of water at 1bar and 100°C is 41kJ mol-1. Calculate the internal energy change, when
(i) 1 mol of water is vaporised at 1 bar pressure and 100°C.
(ii) 1 mol of water is converted into ice.
For an isolated system, delta U = 0; what will be delta S?
The combustion of one mole of benzene takes place at 298 K and 1 atm. After combustion, CO2(g) and H2O (1) are produced and 3267.0 kJ of heat is liberated. Calculate the standard enthalpy of formation, ΔfHΘof benzene. Standard enthalpies of formation of CO2(g) and H2O(l) are -393.5 kJ mol1and 285.83kJ mol1respectively.
difference between state function and state variable?
Why is density an intensive property whereas volume and mass are extensive?
Calculate the amount of heat evolved when[1] 500cm3 of 0.1 M HCl acid is mixed with 200cm3 of 0.2 M NaOH solution [2] 200cm3 of 0.2 M H2SO4 is mixed with 400cm3 of 0.5 M KOH solution. Assuming that the specific heat of water is 4.18 K-1 g-1 ignoring the heat absorbed by the container, therometer, stirrer etc., what would be the rise is temperature in each of the above cases?
How to derive delta H= qv from first law of thermodynamics?
A 5 L cylinder contains 10 moles of oxygen at 27 degrees celsius. Due to sudden leakage through the hole, all the gas escaped into the atmosphere and the cylinder got empty. If the atmospheric pressure is 1 atm, calculate the work done by the gas.
the heat of combustion of benzene in a bomb calorimeter was found to be 3263.9 kj/mol at 25 C.calculate the heat of combustion of benzene at constant pressure?
Calculate the enthalpy change on freezing of 1.0 mol of waterat 10.0°C to ice at –10.0°C. ΔfusH= 6.03 kJ mol–1at 0°C.
Cp[H2O(l)] = 75.3 J mol–1K–1
Cp[H2O(s)] = 36.8 J mol–1K–1
A 10CM COLUMN OF AIR IS TRAPPED BY AN 8CM LONG COLUMN OF Hg in a capillary tube horizontally fixed at 1 atm pressure . calculate the length of air column .when the tube is fixed
a) Vertically with open end up
b) Vertically with open end down
c) At 45o from the horizontal with the open end up .
The enthalpy of combustion of ethyl alcohol is 1380.7 KJ/mol. If the enthalpies of formation of CO2 and H20 are 394.5 and 286.6 KJ/mol. Calculate the enthaply of formation of ethyl alcohol.
Correlate entopy and disorder with the help of fusion and vaporisaton processes.
write the conjugate acid and base of H2O2 ???
For a reaction,both delta H and delta S are positive.under what condition,the reaction occurs spontaneously
standard enthalpies of formation of CO2 and H2O and CH4 are -393.5, -286.2 and 74.8 kJmol-1 respectively. calculate the enthalpy of combustion of methane.
how will we draw a born haber cycle for MgCl2 ?
What is first law of thermodynamics.
Enthalpy of solution (ΔH) for BaCl2 . 2H2O & BaCl2 are 8.8 & -20.6kJ mol-1 reapectively. Calculate the heat of hydration of BaCl2 to BaCl2 . 2H2O................
The molar heat of formation of nh4no3 (s) is -367.54 kj and those of no2(g) is 81.46and h2o(l) is -285.78 kj at 298k and 1.0 atmospheric pressure .Calculate delta H and delta U for the reaction.
Calculate the enthalpy change on freezing of 1.0 mol of waterat 10.0C to ice at 10.0C. ΔfusH= 6.03 kJ mol1at 0C.
Cp[H2O(l)] = 75.3 J mol1K1
Cp[H2O(s)] = 36.8 J mol1K1
Total enthalpy change involved in the transformation is the sum of the following changes:
(a) Energy change involved in the transformation of 1 mol of water at 10C to 1 mol of water at 0C.
(b) Energy change involved in the transformation of 1 mol of water at 0 to 1 mol of ice at 0C.
(c) Energy change involved in the transformation of 1 mol of ice at 0C to 1 mol of ice at 10C.
= (75.3 J mol1K1) (0 10)K + (6.03 × 103J mol1) + (36.8 J mol1K1) (10 0)K
= 753 J mol1 6030 J mol1 368 J mol1
= 7151 J mol1
= 7.151 kJ mol1
Hence, the enthalpy change involved in the transformation is 7.151 kJ mol1.
Pls explain this question i antfigureout wny we have to arry this method plsexplain
an athlete is given 180g of glucose (c6 h12 o6). he utilises 50% of the energy due to internal combustionin the body. In order to avoid storage of energy oin the body, calculate the mass of water he'll need to perspire.
Given enthalpy of combustion of glucose is -2800 kj/mol and enthalipy os evaporation of water is 44kj/mol.
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Syllabus
Noble gases have high positive values of electron gain enthalpy
Standard enthalpy of vapourisation DvapHQ for water at 100° C is 40.66 kJmol–1. The internal energy of vapourisation of water at 100°C (in kJmol–1) is ?
what is the difference between Qc and kc.
calculate the standard enthalpy of formation of ethene (C2H4)from the following equation-
C2H4(g) + 3O2(g)-----》 2CO2 +2H2O enthalpy of formatiom of reaction is -1323 kJ/m
Enthalpy of formation of CO2,H2O and O2 are -393.5 ,-249,0 respectively
The work done in an open vessel at 300 K, when 112 g iron reacts with dil HCl to give FeCl2 is?
Ans 1.2 kcal
a) 0.576 J/K
b) 5.76 J/K
c) 7.56 J/K
d) 2.76 J/K
Calculate the heat evolved at constant volume .
( R = 8.314 J / K mol. )
please explain cp-cv=R briefly
a) (dH/dt)p-(dU/dt)v=R (B) (dH/dt)p > (dU/dt)v (C)(dU/dV) for ideal gas is zero (D)all are correct
calculate the enthalpy of formation of methane
C +O2 --CO2 deltaH = -393.7 KJ/MOL
H2+1/2 O2 ---H2O H= -285.8 KJ/MOL
CH4 +2O2 ---CO2+2H2O H = -890.4 KJ/MOL
2. To what extent do the chemical reactions proceed ?
3. How do we determine the energy changes involved in a chemical reaction? will it occur or not ?
Derive Gibbs Energy change and non mechanical work.
6C + 2H2 gives C6H6
The standard enthalpy of combustion of Benzene is -3266.0 kJ and standard enthalpy of formation of CO2 and H2O are -393.1 kJ and -286.0 kJ respectively.
Why does a liquid boils at a lower temperature at the top of a mountain than at sea level?
derive the relationship between delta H and delta U for an ideal gas .explain each term involved in the equation.
what is the value of (delta) ng for the following reaction :-
H2(g) + I2(g) -- 2HI(g)
Which of the following process when carried out at a constant pressure can have value of w to be positive ?
Sn + 2 F2 --------- Sn F4
PCl5-------- PCl3 + cl2
C+ O2-------CO2
CaCO3------------CaO + CO2
THE HEAT OF COMBUSTION OF METHANE AT CONSTANT VOLUME IS MEASURED IN A BOMB CALORIMETER AT 298K AND IS FOUND TO BE -885KJ/MOL. CALCULATE THE HEAT OF COMBUSTION AT COSTANT PRESSURE.
If enthalpy of a reaction CH2Cl2 (g) --- C (g) + 2H (g) + 2Cl (g) is 1482 kJ/mol and bond dissociation enthalpy of (C-H) bond is 415 kJ/mol than bond dissociation enthalpy of (C-Cl) bond is
A spherical balloon of 21 cm diameter is to be filled up with hydrogen at NTP from a cylinder containing the gas at 20 atm. at 27 degree celcius. If the cylinder can hold 2.82 litres of water, calculate the numbers of balloons that can be filled up ?
a) open system
b) closed system
c) isolated system
d) none of the above
what is atomicity of gas?explain briefly
Find the difference between heats of reaction at constant pressure and constant volume for the following reaction at 25 C in kJ.
2C6H6 + 15O2 ---------> 12CO2 + 6H2O.
why change in volume is area * displacement??
What do you mean by Cp and Cv. Derive the relation between Cp and Cv.
(g) + 1/2 (g) O () + , kJ/mol
(g) + 1/2 (g) O (g) + kJ/mol
Compare the magnitude of and : ( and are the heat released in above two processes)
Why delta v is negative?
Derive Cp- Cv = R.
Predict the feasibility of a reaction when
(i) both delta H and delta S increases.
(ii)both delta H and delta S decreases.
(iii)delta H increases but delta S decreases.
(iv)delta H decreases but delta S increases.
calculate the enthalpy of the reaction of C2H4(g)+H2(g) give rise to C2H6(g)from the the following data??
pls fast urgent I want it within 2hrs????pls plsssssssss help
what is the use of stirrer in these calorimeters..
Calorific valueof ethane, in kJ/g if for the rxn
2C2H6 + 7O2--- 4CO2 + 6H2O + 745.6 kcal
Ans -52
How?
A) ETHYLENE
B) PROPYLENE
C) 1:1 MIXTURE OF TWO GASES
how to convert Ethyne to acetaldehyde ?
How Vf − Vi can be negative ? plz explain
If water vapour is assumed to be a perfect gas, molar enthalpy change for vapourisation of 1 mol of water at 1bar and 100°C is 41kJ mol-1. Calculate the internal energy change, when
(i) 1 mol of water is vaporised at 1 bar pressure and 100°C.
(ii) 1 mol of water is converted into ice.
For an isolated system, delta U = 0; what will be delta S?
The combustion of one mole of benzene takes place at 298 K and 1 atm. After combustion, CO2(g) and H2O (1) are produced and 3267.0 kJ of heat is liberated. Calculate the standard enthalpy of formation, ΔfHΘof benzene. Standard enthalpies of formation of CO2(g) and H2O(l) are -393.5 kJ mol1and 285.83kJ mol1respectively.
and , both of which are removed and the removal of water generates oxygen for breathing by the
reaction
4(s) + 2(l) -> 3(g) + 4KOH(s)
The potassium hydroxide removes from the apparatus by the reaction :
KOH (s) + (g) --> KH(s)
(a) What mass of generates 20 gm of oxygen ?
(b) What mass of can be removed from the apparatus by 100 gm of ?
difference between state function and state variable?
Why is density an intensive property whereas volume and mass are extensive?
Calculate the amount of heat evolved when[1] 500cm3 of 0.1 M HCl acid is mixed with 200cm3 of 0.2 M NaOH solution [2] 200cm3 of 0.2 M H2SO4 is mixed with 400cm3 of 0.5 M KOH solution. Assuming that the specific heat of water is 4.18 K-1 g-1 ignoring the heat absorbed by the container, therometer, stirrer etc., what would be the rise is temperature in each of the above cases?
Derive Gibbs Energy change and non mechanical work.
1)0.6 2)0.3 3) 2 4)6
How to derive delta H= qv from first law of thermodynamics?
A 5 L cylinder contains 10 moles of oxygen at 27 degrees celsius. Due to sudden leakage through the hole, all the gas escaped into the atmosphere and the cylinder got empty. If the atmospheric pressure is 1 atm, calculate the work done by the gas.
the heat of combustion of benzene in a bomb calorimeter was found to be 3263.9 kj/mol at 25 C.calculate the heat of combustion of benzene at constant pressure?
1)the enthalpy decreases
2)the enthalpy increases
3)the enthalpy remains unchanged
4)the internal energy decreases
Calculate the enthalpy change on freezing of 1.0 mol of waterat 10.0°C to ice at –10.0°C. ΔfusH= 6.03 kJ mol–1at 0°C.
Cp[H2O(l)] = 75.3 J mol–1K–1
Cp[H2O(s)] = 36.8 J mol–1K–1
A 10CM COLUMN OF AIR IS TRAPPED BY AN 8CM LONG COLUMN OF Hg in a capillary tube horizontally fixed at 1 atm pressure . calculate the length of air column .when the tube is fixed
a) Vertically with open end up
b) Vertically with open end down
c) At 45o from the horizontal with the open end up .
From the table above, since (delta)S and (delta)H are NEGATIVE, at low temperatures, the reaction will be spontaneous i.e, rate of reaction is VERY quick. Thus, rate of reaction will increase with DECREASE in temperature (Option B).
But the answer says option A- R/O Rxn will increase with INCREASE in temperature. I can't understand the explanation.
Could someone explain why? Am I correct or not?
FAST!! :-)
The enthalpy of combustion of ethyl alcohol is 1380.7 KJ/mol. If the enthalpies of formation of CO2 and H20 are 394.5 and 286.6 KJ/mol. Calculate the enthaply of formation of ethyl alcohol.
Correlate entopy and disorder with the help of fusion and vaporisaton processes.
write the conjugate acid and base of H2O2 ???
For a reaction,both delta H and delta S are positive.under what condition,the reaction occurs spontaneously
HCl + NaOH --> NaCl + H2O + x cal
H2SO4 + 2NaOH --> Na2SO4 + 2H2O + y cal
(1) x = y
(2) x = 2y
(3) x = y/2
(4) x2 = y
standard enthalpies of formation of CO2 and H2O and CH4 are -393.5, -286.2 and 74.8 kJmol-1 respectively. calculate the enthalpy of combustion of methane.
how will we draw a born haber cycle for MgCl2 ?
What is first law of thermodynamics.
&
How is qp = Delta(H)? where, qp represents heat at constant pressure.
Enthalpy of solution (ΔH) for BaCl2 . 2H2O & BaCl2 are 8.8 & -20.6kJ mol-1 reapectively. Calculate the heat of hydration of BaCl2 to BaCl2 . 2H2O................
The molar heat of formation of nh4no3 (s) is -367.54 kj and those of no2(g) is 81.46and h2o(l) is -285.78 kj at 298k and 1.0 atmospheric pressure .Calculate delta H and delta U for the reaction.
Calculate the enthalpy change on freezing of 1.0 mol of waterat 10.0C to ice at 10.0C. ΔfusH= 6.03 kJ mol1at 0C.
Cp[H2O(l)] = 75.3 J mol1K1
Cp[H2O(s)] = 36.8 J mol1K1
Answer:Total enthalpy change involved in the transformation is the sum of the following changes:
(a) Energy change involved in the transformation of 1 mol of water at 10C to 1 mol of water at 0C.
(b) Energy change involved in the transformation of 1 mol of water at 0 to 1 mol of ice at 0C.
(c) Energy change involved in the transformation of 1 mol of ice at 0C to 1 mol of ice at 10C.
= (75.3 J mol1K1) (0 10)K + (6.03 × 103J mol1) + (36.8 J mol1K1) (10 0)K
= 753 J mol1 6030 J mol1 368 J mol1
= 7151 J mol1
= 7.151 kJ mol1
Hence, the enthalpy change involved in the transformation is 7.151 kJ mol1.
Pls explain this question i antfigureout wny we have to arry this method plsexplain
an athlete is given 180g of glucose (c6 h12 o6). he utilises 50% of the energy due to internal combustionin the body. In order to avoid storage of energy oin the body, calculate the mass of water he'll need to perspire.
Given enthalpy of combustion of glucose is -2800 kj/mol and enthalipy os evaporation of water is 44kj/mol.
(ii) Expansion occurs against a constant external pressure of 202.65 kPa. (iii) Expansion is free.