Chemistry - Online Test
Q1. Which of the following is an amphoteric oxide?
Answer : Option A
Explaination / Solution:
Higher oxidation state oxides are acidic while lower oxidation state oxides are basic. Intermediate oxidation state oxides are amphroteric.
Q2. Dislocation defect is also known as
Answer : Option D
Explaination / Solution:
In frenkel defect cation gets dislocated from its position.
Q3. Which metal is used in paints and lacquers?
Answer : Option C
Explaination / Solution:
Al is generally used in paints and lacquers.
Q4. If change in Gibbs energy ΔG is negative (< 0) at constant pressure and temperature
Answer : Option B
Explaination / Solution:
ΔG gives a criteria for spontaneous and non spontaneous process at constant temperature and pressure. ΔG < 0 (negative) means reaction is spontaneous and ΔG >0 (positive) means reaction is non spontanenous.
Q5. Ionization enthalpy increases across a period because
Answer : Option C
Explaination / Solution:
Consider moving from lithium to fluorine across the second period, where successive electrons are added to orbitals in the same principal quantum level. The shielding of the nuclear charge by the inner core of electrons does not increase very much to compensate for the increased attraction of the electron to the nucleus. Thus, across a period, increasing nuclear charge outweighs the shielding. Consequently, the outermost electrons are held more and more tightly and the ionization enthalpy increases across a period.
Q6. According to Pauli’s exclusion principle
Answer : Option A
Explaination / Solution:
The Pauli Exclusion Principle states that, in an atom or molecule, no two electrons can have the same four electronic quantum numbers. As an orbital can contain a maximum of only two electrons, the two electrons must have opposing spins.
Q7. Recycling of materials and energy will lead to :
Answer : Option C
Explaination / Solution:
Recycling of materials and energy will lead to decrease in environmental pollution as amount of waste material will be lesser and so lesser pollution will be caused.
Q8. Which of the following compound is amphoteric?
Answer : Option A
Explaination / Solution:
Cr(OH)3 is amphroteric.
Q9. The number of moles of solute present in 1 kg of solvent is called--------------.
Answer : Option D
Explaination / Solution:
Molality is defined as no. of moles of solute present per kg of solvent.It is denoted as " m " . Mathematically ,
Molality (m)
= [ number of moles of the solute ] / kg of solvent
Since , this mode of expressing the strength of a solution involves ( weight / weight ) relationship of solute and solvent , the molality of the solution is not affected by variation in temperatures of the solution.
Q10. Which of the following acids does not exhibit optical isomerism?
Answer : Option D
Explaination / Solution:
Maleic Acid shows Geometrical Isomerism but does not give optical isomerism.
