The enthalpies of all elements in their ...

The enthalpies of all elements in their standard states are

unity

zero

`lt 0`

different for each element.

Text Solution

Verified by Experts

The correct Answer is:

zero

Topper's Solved these Questions

CHEMICAL THERMODYNAMICS
ICSE|Exercise NUMBERICAL PROBLEMS|18 Videos
CHEMICAL BONDING AND MOLECULAR STRUCTURE
ICSE|Exercise NCERT TEXT-BOOK EXERCISES ( WITH HINTS AND SOLUTIONS)|47 Videos
CLASSIFICATION OF ELEMENTS AND PERIODICITY IN PROPERTIES
ICSE|Exercise NCERT TEXT-BOOK. EXERCISE (With Hints and Solutions)|63 Videos

Similar Questions

Explore conceptually related problems

Assertion (A). Combustion of all organic compounds is an exothermic reaction. Reason (R). The enthalpies of all elements in their standard state are zero

The enthalpies of the elements in their standard states are arbitrarily assumed to be

The enthalpies of elements in their standard states are taken as zero. The enthalpy of formation of a compound

The enthalpy of elements in their standard states are taken as zero .The enthalpy of formation of a compound:

Statement -1: The Standard free energy changes of all spontaneously occurring reactions are negative . Statement-2: The standard free energies of the elements in their standard states at 1 bar and 2985K aare taken aszero.

Since the enthalpy of elements in their natural state is taken to be zero, the heat of formation (Delta_(f)H) of compounds

What is the enthalpy of formation of the most stable form of an element in its standard state ?

The conventional standard molar enthalpy of an element in its stable state of aggregation at 298K is taken to be ……………. .

Statement-1 : Entropy of all elements is zero at zero Kelvin. Statement-2 : Standard entropy of all elements is greater than zero. Statement-3 : Entropy of all elements and compounds decreases with decrease of temperature and becomes zero at absolute zero temperature.

Why are the second ionisation enthalpies of group 1 elements much higher than their first ionisation enthalpies ?

ICSE-CHEMICAL THERMODYNAMICS -NCERT TEXT-BOOK. EXERCISES

Choose the correct answer. A thermodynamic state function is a quanti...
Text Solution
|
For the process to occur under adiabatic conditions, the correct condi...
Text Solution
|
The enthalpies of all elements in their standard states are
Text Solution
|
DeltaU^@ of combustion of methane is -X kJ mol^(-1). The value of Delt...
Text Solution
|
The enthalpy of combustion of methane, graphite and dihydrogen at 298 ...
Text Solution
|
A reaction A + B toC + D + q is found to have a positive entropy chang...
Text Solution
|
In a process, 701 J of heat is absorbed by a system and 394 J of work ...
Text Solution
|
The reaction of cyanamide, NH(2)CN (s), with dioxygen was carried out ...
Text Solution
|
Calculate the number of kJ of heat necessary to raise the temperature ...
Text Solution
|
The enthalpy change on freezing of 1 mol of water at 5^(@)C to ice at ...
Text Solution
|
Enthalpy of combustion of carbon to CO2 is -393.5 kJ mol^(-1) Calcu...
Text Solution
|
Enthalpies of formation of CO(g).CO(2)(g) and N(2)O(4) are -110,-393,8...
Text Solution
|
Given N(2)(g)+3H(2)(g)rarr2NH(3)(g),Delta(r)H^(Ө)= -92.4 kJ mol^(-1...
Text Solution
|
Calculate the standard enthalpy of formation of CH(3)OH(l) from the fo...
Text Solution
|
Calculate the enthalpy change for the process C CI(4)(g)rarrC(g)+4C...
Text Solution
|
For an isolated system, DeltaU=0, what will be Delta S?
Text Solution
|
For the reaction at 298 K, 2A + B to C DeltaH=400 KJ mol^(-1) an...
Text Solution
|
For the reaction, 2Cl(g) to Cl2(g), what are the signs of DeltaH and D...
Text Solution
|
For the reaction 2A(g)+B(g)rarr2D(g) DeltaU^(theta)=-10.55 KJ and ...
Text Solution
|
The equilibrium constant for a reaction is 10. What will be the value ...
Text Solution
|