Explore topic-wise MCQs in Chemistry.

This section includes 10 Mcqs, each offering curated multiple-choice questions to sharpen your Chemistry knowledge and support exam preparation. Choose a topic below to get started.

1.

Hr = Hf[products] Hf[reactants].

A. true
B. false
Answer» B. false
2.

Which of the following is not an application of Hess s law?

A. determination of heat of formation
B. determination of heat of transition
C. determination of Gibb s energy
D. determination of heat of hydration
Answer» D. determination of heat of hydration
3.

What is the unit of standard enthalpy of fusion or molar enthalpy of fusion?

A. KJ Mol
B. KJ per Mol
C. Mol per KJ
D. 1/KJ Mol
Answer» C. Mol per KJ
4.

Consider the equation 2 H2 + O2 2 H2O, what does the 2 in the coefficient of H2O molecule represent?

A. number of particles
B. the number of molecules
C. number of moles
D. number of atoms
Answer» D. number of atoms
5.

When a chemical reaction is reversed the value of enthalpy is reversed in sign.

A. true
B. false
Answer» B. false
6.

What is a change in energy if 18 grams of water is heated from room temperature to 20 degrees above it?

A. 1.50 KJ
B. 0.506 KJ
C. 1.06 KJ
D. 1.506 KJ
Answer» E.
7.

Calculate the internal energy change when 2 moles of water at 0 degrees converts into ice at 0-degree centigrade?

A. 12 KJ per mole
B. 6 KJ per mole
C. 1 KJ per mole
D. 102 KJ per mole
Answer» B. 6 KJ per mole
8.

Consider that, a ball is immersed in water at room temperature and then taken out having 18 grams of water on it, how much amount of energy is required to dry that water at room temperature?

A. 41.43 KJ/mol
B. 49.53 KJ/mol
C. 41.3 KJ/mol
D. 41.53 KJ/mol
Answer» E.
9.

All the enthalpies of fusion are positive.

A. true
B. false
Answer» B. false
10.

The standard state of a substance is considered when the temperature is 298 k and the pressure is ____________

A. 1 ATM
B. 1 bar
C. 1 Pascal
D. 760 mm HG
Answer» C. 1 Pascal