Solved Past Papers MCQs of MDCAT for the preparation of Medical and Dental College Admission Test and other medical tests.
Q.51 The ability of an atom in a covalent bond to attract the bonding electrons is called:
A) Ionization energy C) Electronegativity
B) Ionic bond energy D) Electron affinity
Q.52 The paramagnetic character of a substance is due to:
A) Bond pairs of electrons C) Unpaired electrons in atom or molecule
B) Lone pairs of electrons D) Paired electrons in valence shells of electrons
Q.53 Lattice energy of an ionic crystal is the enthalpy of:
A) Combustion C) Dissolution
B) Dissociation D) Formation
Q.54 In standard enthalpy of atomization, heat of the surrounding:
A) Remains unchanged C) Increases than decreases
B) Increases D) Decreases
Q.55 Mole fraction of any compound us the ratio of moles of all components in a:
A) Compound C) Molecule
B) Solution D) Solid
Q.56 Molarity is defined as the number of moles of any substance dissolved:
A) Per dm3 of water C) Per m3 of water
B) In one gram of water D) In 100 ml of water
Q.57 In electrolytic cell, a salt bridge is used in order to:
A) Pass the electric current C) Mix solution of two half cells
B) Prevent the flow of ions D) Allow movement of ions b/w two half cells
Q.58 In all oxidation reactions, atoms of an element in a chemical species lose electrons and increase their:
A) Oxidation states C) Electrode
B) Reductions D) Negative charges
Q.59 In ‘AgCl’ solution. Some salt of NaCl is added, ‘AgCl’ will be precipitated due to:
A) Solubility C) Unsaturation effect
B) Electrolyte D) Common ion effect
Q.60 ‘Ka’ for an acid is higher, the stronger is the acid; relate the strength an acid with ‘pKa’
A) Higher pKa, weaker the acid C) pKa has no relation with acid strength
B) Lower pKa, stronger the acid D) Both A and B
Q.61 It is experimentally found that a catalyst is used to:
A) Lower the activation energy C) Lower the pH
B) Increase the activation energy D) Decrease the temp of the reaction
Q.62 According to collision theory of bimolecular reaction sin gas phase, the minimum amount of energy required for an effective collision is known as:
A) Heat of reaction C) Has no effect on the reaction
B) Rate of reaction D) Energy of activation
Q.63 Carbon exists as allotropes, which are different crystalline or molecular forms of the same substance. Graphite and diamond are allotropes of carbon. Diamond is a non-conductor whereas graphite is a good conductor because:
A) Graphite has a layered structure C) In graphite one of valence electron is free to move
B) In graphite, all valence electrons are tetrahedrally D) Graphite is soft and greasy bound
Q.64 The presence of calcium is essential for the normal development of plants. An adequate supply of calcium appears to stimulate the development of which part of the plants?
A) Leaves C) Root hairs
B) Fruits D) Branches
Q.65 When elements of group II-A (alkaline earth metals) are exposed to air, they quickly become coated with a layer of oxide. What is the purpose of this oxide layer?
A) The oxide layer exposes the metal to Atmospheric attack
B) The oxide layer increases the reactivity of metal
C) The oxide layer protects the metal from further atmospheric attack
D) The oxide layer gives the metal a shiny silvery appearance
Q.66 In silicon dioxide each silicon atom is tetrahedrally bonded to four oxygen atoms and each oxygen atom is bonded to two silicon atoms. The ratio of silicon to oxygen atoms is:
A) 2:2 C) 2:1
B) 1:2 D) 1:4
Q.67 Hydrogenation of unsaturated oils is done by using:
A) Finally divided nickel C) Vanadium pentaoxide
B) Finally divided iron D) Copper
Q.68 Pick the correct statement:
A) Chelates are usually more stable than ordinary C) Monodentate ligands form the chelates complexes
B) Ordinary complexes are more stable than chelates D) Chelates have no ring structures
Q.69 In contact process, the catalyst used for the conversion of Sulphur dioxide to Sulphur trioxide is:
A) Magnesium oxide C) Silicon dioxide
B) Aluminum oxide D) Vanadium pentoxide
Q.70 The unpolluted natural rain water is slightly acidic due to the reaction of rain water with:
A) Sulphur dioxide C) Carbon dioxide
B) Oxides of nitrogen D) Hydrogen present in air
Q.71 In the Haber’s process for the manufacturing of ammonia, nitrogen is taken from:
A) Proteins occurring in living bodies C) Air
B) Ammonium salts obtained industrially D) Mineral containing nitrates
Q.72 In comparison with oxygen gas, a strong triple bond is present between two nitrogen atoms in a molecule and therefore nitrogen gas is:
A) Highly reactive gas C) Very less reactive gas
B) Completely inert like noble gases D) Moderately reactive gas
Q.73 The compound with an atom, which has unshared pair of electrons is called:
A) Nucleophile C) Protophile
B) Electrophile D) None of the above
Q.74 1-chloropropane and 2-chlorpropane are isomers of each other, the type of isomerism in these two is called:
A) Cis-trans isomerism C) Position isomerism
B) Chain isomerism D) Functional group isomerism
Q.75 Benzene in the presence of AlCl3 produces acetophenone when reacts with:
A) Acetyl chloride C) Ethyl benzene
B) Acetic acid D) Ethanoic acid
READ MORE:
- Solved Past Papers MCQs of MDCAT 1
- Solved Past Papers MCQs of MDCAT 2
- Solved Past Papers MCQs of MDCAT 3
