Chemistry MDCAT Unit-6 Past Paper PDF

CHEMISTRY MDCAT UNIT–6 (A + SERIES) TOPIC:-  CHEMICAL BONDING Q.1 What is the exact value of angle in BF3 A. 90° B. 104.5° C. 119.5° D. 120° Q.2 Which of...

CHEMISTRY MDCAT UNIT–6 (A + SERIES) TOPIC:-  CHEMICAL BONDING Q.1 What is the exact value of angle in BF3 A. 90° B. 104.5° C. 119.5° D. 120° Q.2 Which of the following sets constitutes of all the molecules and ions of non-planar geometry? A. SO 2 ,C2 H 4 ,BF3 ,NO3 B. CH 4 ,NH 4 ,MnO 4 ,NF3 C. CH  CH,H2O,BeCl2 ,H2S D. PH 4 ,NH3 ,SO3 ,Benzene Q.3 When the two partially filled atomic orbital overlap in such a way that the probability of finding the electron is maximum around the line joining the two nuclei, the result is the formation of A. Sigma bond B. Hydrogen bond C. Pi-bond D. Metallic bond Q.4 The angle between un-hybridized p-orbital and three sp2 hybrid orbitals of each carbon atom is A. 120o B. 109.5o o C. 90 D. 180o +2 Q.5 Fe will from the most ionic bond with A. N-3 B. SN-3 -3 C. P D. F-1 Q.6 AB4 type with no lone pairs geometry enables to form which shape of molecule? A. Trigonal B. Regular octahedral C. Regular tetrahedral D. Regular pyramidal Q.7 Which of the following has greatest difference of electronegativity? A. HF B. HCl C. HBr D. Hl Q.8 Identify the compound given below which has bond formed by overlapping of sp 2 and p orbital: A. BeCl2 B. BF3 C. H2O D. NH3 Q.9 During the formation of chemical bond A. Energy decreases B. Energy increases C. Energy does not change D. Energy first decreases then increases Q.10 Which of the following is not a primary bond? A. Ionic bond B. Hydrogen bond C. Dative bond D. Covalent bond Q.11 All of the following are co-planar molecules except A. Propyne B. Ethyne C. Benzene D. Ethene Q.12 Which of the following types of bonds has the least electronegativity difference between the bonding atoms? A. Ionic bond B. Polar covalent bond C. Nonpolar covalent bond D. Hydrogen bond Q.13 Which of the following has lowest first ionization energy A. Ne B. F C. N D. O Q.14 The percentage of ionic and covalent character in HF is A. 20, 80 B. 80, 20 C. 57, 43 D. 43, 57 CHEMISTRY MDCAT UNIT-6 (A+SERIES) PAGE 1 OF 4 Q.15 Which of the following is non-polar but contains polar bonds? A. HCl B. H2O C. CCl4 D. SO2 Q.16 The compromised distance between two hydrogen atoms in hydrogen molecule is A. 75.4 pm B. 134 pm C. 139 pm D. 120 Q.17 The radius of an atom cannot be measured precisely because A. Atom has no sharp boundary B. Size of atom changes from one compound to other C. Finding probability of electrons never becomes zero D. All of the above Q.18 The half of __________ bond between two similar atoms covalently bonded in a molecule is called covalent radius A. Single B. Double C. Triple D. All of these Q.19 The ionization energies of III-A and VI-A show abnormal trend while moving left to right in a period, can be best explained by A. Atomic radius B. Nuclear charge C. Shielding effect D. Mode of electronic configuration Q.20 The elements of ___ , _____ and ______ show abnormally low values of electron affinity in every period A. II-A , V-A , VIII-A B.I-A , V-A , VI-A C. III-A , VI-A , VIII-A D. I-A , II-A , III-A Q.21 The tendency of an atom to _______________ is called electronegativity A. Donate electron pair B. Share electron pair C. Gain electron pair D. Attract shared electron Q.22 In ammonium ion the bond angle is equal to A. NF3 B. H2S C. CCl4 D. CO2 Q.23 Which of the following specie contains only sp–hybridized carbon atom A. Hydrogen cyanide B. Propyne C. Vinyl alcohol D. 1,3-Butadiene Q.24 In which of the following central atom can form dative bond with NH3 A. MgCl2 B. PH4+ C. BH3 D. CH4 Q.25 Which of the following pair has same geometry but different bond angle A. SiO2 and SO2 B. H2S and CS2 C. BeCl2 and CO2 D. H2S and H2O Q.26 Which of the following halogen has almost same bond energy A. F2 and Cl2 B. F2 and I2 C. Cl2 and Br2 D. Br2 and I2 Q.27 Which atomic numbers in periodic table represent the elements that generally show abnormal trends in ionization energy A. 12 and 16 B. 13 and 16 C. 20 and 15 D. 11 and 12 Q.28 Which of the following represents the correct arrangement of atoms according to their atomic radii? A. Mg < Ca < Sr B. Mg < Sr < Ca C. Sr < Ca < Mg D. Mg < Ca < Be Q.29 Which of the following specie has largest ionic radius A. F– B. F 2– C. O D. N3– Q.30 Which one of the following molecules has minimum value of bond angle? A. SiH4 B. NF3 C. BH3 D. CO2 CHEMISTRY MDCAT UNIT-6 (A+SERIES) PAGE 2 OF 4 Q.31 The correct ascending order of electron affinity is A. I > F > Cl B. I < F < Cl C. I > Cl > F D. I < Cl < F Q.32 Which one of the following species shows maximum types of van der waal’s repulsions? A. H2S B. NF3 + C. H3O D. NH4+ Q.33 According to VSEPR theory ________________ does not belong to AB4 type A. H2S B. BF3 C. BH4– D. NH4+ Q.34 H3O+ contains (I) Electrovalent bond (II) Dative bond (III) Covalent bond A. I, II and III B. I and II C. II only D. II and III Q.35 The bond angle 107o is present in A. NH3 B. AlH3 C. NF3 D. NH4+ Q.36 Which order of IE is incorrect A. Ba < Sr < Ca B. Al < Si < P C. B < Be < C D. Si < N < O Q.37 The energy gap between 2nd ionization energy and 3rd ionization energy is very large, it is true for an element having ___________ Z values belonging to ___________ A. 11, I-A B. 12, II-A C. 13 , III-A D. 14 , IV-A Q.38 Select the specie that have different shape than others A. H 3O + B. NH3 C. BF3 D. NF3 Q.39 The central atom of which of the following class of molecules carries bond pair – bond pair repulsions only A. AB2 B. AB3 C. AB4 D. AB5 Q.40 The percentage of s-character in hybrid orbital which indicates longest bond length A. 25% s-character B. 33.4% s-character C. 50 % s-character D. 75% s-character Q.41 What is the hybridization of carbon number 1 in 1-Propene A. sp3 B. sp2 C. sp D. dsp2 Q.42 If a molecule has 3 bond pair and 1 lone pair then its molecular geometry will be A. Linear B. Tetrahedral C. Trigonal planar D. Trigonal pyramidal Q.43 The shape of carbonate ion is A. Square planar B. Trigonal pyramidal C. Trigonal planar D. Tetrahedral Q.44 Select the specie that contains maximum number of bond pairs A. CO2 B. H2O C. NH3 D. BeH2 Q.45 Which one of the following species contains no lone pair? A. NH4+ B. H3O+ C. NH3 D. Both A and B Q.46 The high value of first ionization energy of nitrogen than that of oxygen is due to its A. High value of Z B. Low value of mass number C. Increased shielding effect D. Half-filled p – subshell CHEMISTRY MDCAT UNIT-6 (A+SERIES) PAGE 3 OF 4 Q.47 Choose the true statement. A. Along a period from left to right, atomic radius increases. B. Along a period from left to right, ionization energy decreases. C. Electronegativity of elements increases from left to right along a period. D. None of the above Q.48 Ammonia (NH3) can form bond with boron trifluoride (BF3). For the bond formation, the electrons are most likely supplied by A. Nitrogen B. Boron C. Hydrogen D. Mutual shared by B and N Q.49 The bond between carbon and oxygen in CO2, is most likely to be a / an A. Ionic bond B. Covalent bond C. Hydrogen bond D. Dative bond Q.50 The strength of bond between two atoms depends upon A. Electronegativity difference B. Bond length C. Atomic radius D. All of the above Q.51 The shortening of bonds is due to the predominant participation of _______ orbital in hybridization A. s B. p C. d D. f Q.52 Which of the following element has highest electronegativity A. O B. F C. N D. Cl Q.53 Which of the following electronegativity difference suggests that the bond would be ionic in nature A. 0 – 0.4 B. 0.5 – 1.6 C. Greater than 1.7 D. Cannot be predicted Q.54 Select the specie that has highest ionic character A. CsF B. NaCl C. HF D. KCl Q.55 The bond in fluorine molecule is formed by the overlapping of ___________ on each atom of fluorine atom A. sp3 – orbital B. sp2 – orbital C. s – orbital D. 2pz – orbital Q.56 The carbon-carbon sigma bond in ethyne molecule, is formed by overlapping between orbitals of carbon atoms A. sp2 B. sp C. sp3 D. 2pz Q.57 H–O–H bond angle in H2O is 104.5° and not 109° because of more space occupied by A. High electronegativity of oxygen B. Bond pair – bond pair C. Lone pair – lone pair D. Lone pair – bond pair Q.58 % age of ionic character in the compound can be calculated by   A. ionic  100 B. obs  100 obs ionic  obs C. ionic  1000 D.  1000 obs ionic Q.59 Total number of sigma and pi bonds in vinyl alcohol are A. 5 sigma and 1 pi B. 6 sigma and 1 pi C. 5 sigma and 2 pi D. 6 sigma and 2 pi Q.60 Which of the following will have the highest bond energy? A. A carbon-carbon bond in ethane B. A carbon-carbon bond in ethene C. A carbon-carbon bond in ethyne D. A carbon-carbon bond in benzene CHEMISTRY MDCAT UNIT-6 (A+SERIES) PAGE 4 OF 4