ORG CHEM Flashcards
Which among the following chemical bond were
described by Kossel and Lewis?
a) Metallic bond
b) Polar covalent bond
c) Coordinate bond
d) Ionic and Covalent bond
d) Ionic and Covalent bond
State whether the given statement is true or false “Ionic bonds are non-directional”
a) True
b) False
a) True
If a bond is made up of a large number of organic
compound, then the bond is termed as?
a) Ionic bond
b) Metallic bond
c) Covalent bond
d) Dipolar bond
c) Covalent bond
Which among the following is not an example of
hydrogen bond?
a) H20
b) Liquid HCl
c) NH3
d) CHCl3
b) Liquid HCl
Atoms undergo bonding in order to ?
a) Attain stability
b) Lose stability
c) Move freely
d) increase energy
a) Attain stability
An atom differs from its ion in which among the
following ?
a) Mass number
b) Atomic number
c) Neutrons
d) Number of protons
d) Number of protons
Which among the following is both a molecule and a
compound?
a) C6 H12 O6
b) H2O
c) CO2
d) NaCl
b) H2O
Bond energy and the corresponding bond length vary
directly with each other. comment whether the statement
is true or false.
a) True
b) False
b) False
The energy which must be transferred to any atom to
dislodge an electron is called?
a) Free energy
b) Ionization Energy
c) Quantum mechanical energy
d) Dissociation Energy
b) Ionization Energy
Potassium Ion K+ has the same electronic configuration
as that of which noble gases mentioned below ?
a) Krypton
b) Xenon
c) Argon
d) Radon
c) Argon
Ten covalent bonds in the Lewis structure of Propane
will account for how many valence electrons?
a) 10
b) 20
c) 14
d) 12
b) 20
What is the hybridization of oxygen in water?
a) sp
b) sp2
c) sp3
d) sp3d
c) sp3
The electronegativity difference between the covalently
bonded atoms is
a) Less than 0
b) 0-0.3
c) 0.3-1.7
d) Over 1.7
b) 0-0.3
What is the hybridization of Carbon atom in CF4?
a) sp2
b) sp
c) sp3d
d) sp3
d) sp3
Which one has zero dipole moment?
a) C6H6
b) NH3
c) H2S
d) NO
Answer: a
Explanation: The ring of benzene is completely closed and
is of perfect stability and hence it has zero dipole moment.
Which one have both sigma and pi bonds?
a) H2S
b) NO2
c) HClO
d) NaCN
Answer: d
Explanation: In NaCN both double bond and triple bond is
present and hence it has both sigma
and pi bonds.
PH3, So3, and HF are examples of polar molecules. State
true or false
a) True
b) False
Answer: b
Explanation: SO3 is not an example of polar molecule as it
does not contain a hydrogen bond.
What is the hybridization of sulphur in H2S?
a) sp
b) sp2
c) sp3
d) sp3d
Answer: c
Explanation: S has two pairs of electrons and two atoms
bonded to H with a total of 4 electrons and hence it has a
hybridization of sp3.
Name the geometry of the central oxygen atom in the
ozone molecule (o3)
a) Trigonal planar
b) Linear
c) Tetrahedral
d) Pyramidal
View Answer
Answer: a
Explanation: It forms a single bond with one oxygen atom,
double bond with another oxygen atom and there exists
one more non-bonded atom. Thus, it forms a trigonal
planar structure.
In which molecule there is a complete linear
arrangement of all atoms?
a) BF3
b) NH3
c) CO2
d) CH4
Answer: c
Explanation: BF3 has trigonal planar structure,NH3 has a
trigonal bipyramidal structure, CH4 has tetragonal
structure and hence CO2 is the one with linear structure.
Choose the one which is incorrect
a) BrO4 – tetrahedral
b) PF3 – pyramidal
c) ClO4 – tetrahedral
d) BeBr2 – linear
Answer: b
Explanation: PF3 has a trigonal pyramidal structure as it
has three bonding pairs and one non-bonding pair
A crystalline solid possess which one of the following
property?
a) Irregularity
b) Non- symmetric
c) Perfect geometric pattern
d) non- stability
Answer: c
Explanation: A crystalline solid is one which possesses
perfect geometry, high stability, symmetric and regularly
arranged.
Melting is process which can be stated by the below
statements except,
a) Change from a highly disordered stated to an ordered
state
b) Change from particles in crystal lattice to liquid state
c) Thermal energy of particles overcome the
intercrystalline forces that hold them
d) Change from low temperature to high temperature
Answer: a
Explanation: Melting is a process which proceeds by
changing from a highly ordered state to a disordered state.
Which among the following statement is not true?
a) In liquid, particles are less regularly arranged and are
free to move
b) Boiling involves breaking up of group of molecules in
liquid
c) Boiling involves clubbing of oppositely charged ions
d) Thermal energy of particles overcome cohesive forces
that hold them
Answer: c
Explanation: Boiling involves separation of oppositely
charged ions and makes them as individual ions
Which among the following is not associated with
intermolecular forces?
a) They hold neutral molecules
b) Non- electrostatic in nature
c) attraction of oppositely charged particles
d) dipole-dipole interaction and van der Waals forces
Answer: b
Explanation: Intermolecular forces are electrostatic in
nature.
When one of the Hydrogen in Methane( CH4) is
replaced by a hydroxyl group, then structurally methane
resembles?
a) Methanol
b) Ethanol
c) Water
d) Both methanol and water
Answer: d
Explanation: Like water, it is a liquid with boiling point
which is abnormally high for a compound of its size and
polarity.
Which among the following does not match with the
term solubility?
a) The structural units get separated from each other
b) The ion-dipole bond is very strong
c) The spaces in between the structures are occupied by
solvent molecules
d) The electrostatic attraction between the oppositely
charged ions and their corresponding ends are called iondipole bond
Answer: b
Explanation: The bond is weak but in the aggregate they
supply enough energy to overcome the interionic forces.
A Strong acid is same as concentrated acid. State true or
false
a) False
b) True
Answer: a
Explanation: Concentration of an acid depends upon the
water content whereas the strength of an acid depends on
dissociation power.
When an acid reacts with a metal, which one of the
following gas is usually liberated?
a) ammonia gas
b) chlorine
c) oxygen
d) Hydrogen gas
Answer: d
Explanation: When metal reacts with acid, a soap bubble is
formed and the bubble contains Hydrogen gas (example:
HCl, H2SO4)
Select the one which is wrongly mapped
a) Sodium carbonate – Washing soda
b) Sodium chloride – common salt
c) Calcium carbonate – slaked lime
d) Sodium hydroxide – caustic soda
Answer: c
Explanation: calcium hydroxide is commonly referred as
slaked lime.
What is the pH of 0.0001 molar HCl solution?
a) 1
b) 2
c) 3
d) 4
Answer: d
Explanation: It has a H+ concentration of 10-4
. The value of
negative exponent(^-4) gives pH value to be 4.
Choose the incorrect option regarding Isomerism:
a) They differ in both physical and chemical properties
b) They have the different molecular formula
c) There are two types of Isomerism : Structural and Stereo
Isomerism
d) Geometric and optical isomerism are two types of
Stereo Isomerism
Answer: b
Explanation: Isomers are compounds that have same
molecular formula.
What will be the product when HNO3 reacts with
NH4OH ?
a) NH4 NO3
b) 2NH4 NO3
c) NH4 (NO3)
Answer: a
Explanation: the reaction takes place as follows:
HNO3 + NH4OH —-> NH4NO3 + H2O.
Find the odd one out:
a) Neutral salt : NaCl
b) Acid salt : CuSO4.5H2O
c) Basic salt: CuCO3.Cu(OH)2
d) Nonhydrated salt: KNO3
Answer: b
Explanation: CuSO4.5H20 is a hydrated salt. An example of
acid salt is NaHCO3.
Isomerism that arises out of the difference in spatial
arrangement of atoms or groups about the doubly bonded
carbon atoms are called? (In specific)
a) Structural Isomerism
b) Stereo Isomerism
c) Geometrical Isomerism
d) Optical Isomerism
Answer: c
Explanation: These geometrical isomers are not mirror
images of each other and they differ in spatial
arrangement from one another.
Isomers with similar groups on the same side are called
as ” trans” isomers. State true or false
a) True
b) False
Answer: b
Explanation: “Trans” isomers are those with similar groups
arranged in opposite direction. The Isomers with similar
groups on the same side are called as “cis” isomers.
Which among the following defines Meso forms of
isomers
a) Meso form is optically inactive due to external
compensation
b) The molecules of the meso isomers are chiral
c) It can be separated into optically active enantiometric
pairs
d) It is a single compound
Answer: d
Explanation: Meso forms of isomers are single compound
and their molecules are achiral
and hence they cannot be separated into pairs.
Which among the following does not exhibit geometric
isomerism
a) 1-hexene
b) 2-hexene
c) 3-hexene
d) 4-hexene
Answer: a
Explanation: Alkenes like 1-hexene when flipped from top
to bottom they have identical structures and also they
have C=CH2 unit which does not exist as cis- trans isomers.
Which among the following is formed when an alcohol is
dehydrated?
a) alkane
b) alkyne
c) alkene
d) aldehyde
Answer: c
Explanation: In elimination reaction, when protic acids
react with alcohol, they lose water molecule to form
alkenes.
A fat on hydrolysis would yield?
a) Glycerol and soap
b) Ethanol and soap
c) Ethanol and glycerol
d) Only soap
Answer: a
Explanation: During saponification process, fat on
hydrolysis will yield glycerol and soap
Which among the following correctly defines
Diastereomer?
a) These have same magnitude but different signs of
optical rotation
b) Nonsuperimposable object mirror relationship
c) These differ in all physical properties
d) Separation is very difficult
Answer: c
Explanation: Diastereomers differ in all physical properties.
The rest of the points are related to Enantiomers.
Ethane is obtained by electrolyzing
a) Potassium formate
b) Potassium succinate
c) Potassium acetate
d) Potassium fumarate
Answer: b
Explanation: By electrolyzing potassium succinate (the
process is generally called Kolbe’s electrolysis), ethane is
obtained.
“Methane is a product of aerobic respiration”. State
true or false
a) False
b) True
Answer: a
Explanation: Methane is the end product of anaerobic
decay of plants due to the breakdown of very complicated
molecules.
Calcium carbide on reaction with water gives?
a) Methane
b) Ethane
c) propane
d) Acetylene
Answer: d
Explanation: CaC2 + H20—-> C2H2 + Ca(OH)2.
The hydrocarbon in which all the 4 valencies of carbon
are fully occupied is called as
a) Alkene
b) Alkyne
c) Alkane
d) Cycloalkane
Answer: c
Explanation: Alkanes , the saturated hydrocarbons are
those in which the carbon atoms are bonded covalently to
each other (fully occupied). Each carbon atom is
tetrahedrally surrounded by H-atoms
Name the process associated with acylation of benzene
a) Friedel craft reaction
b) Wurtz reaction
c) Wurtz fitting reaction
d) Debey Huckel reaction
Answer: a
Explanation: The electrophilic substitution reaction that
takes place between ethanoyl chloride and benzene is
called as Friedel craft reaction
Liquid hydrocarbon is converted into gaseous
hydrocarbon by:
a) Oxidation
b) Hydrolysis
c) Cracking
d) Distillation
Answer: c
Explanation: Under cracking with high temperature, the
liquid form of hydrocarbon is converted into gaseous form
Chlorination of alkanes is an example of
a) Radical
b) Elimination
c) Free radical
d) Addition
Answer: c
Explanation: Free radical chlorination is a reaction that
substitutes a chlorine for a hydrogen on an alkane
When chlorine gas reacts with methane, the product
formed is
a) CHCl
b) CH2Cl
c) CH3Cl
d) CH4Cl
Answer: c
Explanation: Under the influence of UV light or with a temperature of 250-400(degree) chlorine and methane
react vigorously to give hydrogen chloride and
chloromethane (CH3Cl).
Methane reacts more readily with chlorine than with
Fluorine. State true or false
a) True
b) False
Answer: b
Explanation: Methane reacts with chlorine but not as
vigorously as with fluorine. The reactivity order is as
follows: F2 > Cl2 > Br2 >I2.
The methyl chloride undergoes substitution to form
a) CHCl
b) CH2Cl
c) CHCl2
d) CH2Cl2
Answer: d
Explanation: Chloromethane undergoes further
substitution to form hydrogen chloride and
dichloromethane (CH2Cl2).
Identify the one which is not a type of chlorination
a) Free radical chlorination
b) Electrophobic chlorination
c) Ketone chlorination
d) Chlorine addition reaction
Answer: b
Explanation: Electrophobic is not a kind of halogenation. It
is electrophilic chlorination, in which aromatic
substitutions takes place.
Which among the following on chlorination undergoes
substitution at the alkyl group
a) Ethers
b) Hydroxyl groups
c) Carbonyl compounds
d) Carboxylic acids
Answer: a
Explanation: In the absence of sunlight, the alpha
hydrogen of ethers undergoes substitution when treated
with chlorine.
In the presence of red phosphorous, chlorine converts
the fatty acids having alpha hydrogen atoms into
a) Halo acids
b) Alpha-halo acids
c) Alpha,alpha-dihalo acids
d) Trihalo acids
Answer: b
Explanation: The propionic acid, in the presence of Cl2/P
gets converted into alpha chloro propionic acid due to the
action of the halogen chlorine.
Chlorine in the presence of which among the following
generates positively charged species?
a) Ferric chloride
b) Anhydrous ferric chloride
c) Ferrous chloride
d) Anhydrous ferrous chloride
Answer: b
Explanation: Ferric chloride is a lewis acid catalyst and in
the presence of chlorine, it converts nitrobenzene into 3-
chloro nitro benzene.