MDCAT Chemistry Online Test With Answers

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MDCAT Chemistry Online Test

Sr. # Questions Answers Choice
1 The geometry of diamonds is tetragonal cubic rhombohedral none of these
2 The molecules of CO2, in dry ice form the covalent crystals molecular crystals none of these crystals ionic crystals
3 The nature of crystal of diamond is metallic molecular covalent ionic
4 The crystals formed due to London forces of interaction are ionic covalent molecular metallic
5 In most of the cases the molecular crystals are very soft soft extremely hard sufficiently hard
6 The crystal of diamond is ionic molecular covalent metallic
7 Substance that does not show the process of sublimation is K2Cr2O7 iodine naphthalene NH4CI
8 The number of Na+, ions which surround each Cl- ion in the NaCl crystal lattice is 8 12 6 10
9 NaCI has face centered cubic structure. The Na ion at the face of the unit cell is shared by 2-unit cells 4-units cells only one unit cell 8-unit cells
10 The Cl- ion present at the corner of the unit cell is NaCl crystal, contributes 1/8 th 1/4 th 1/2 th 1
11 The number of Cl- ions per unit cell of NaCl are 6 4 2 8
12 lonic solids don't conduct the electrical current because ion do not have translatory motion free electrons are less the coordination number of the ion is very high strong covalent bonds are present in their structure
13 lonic solids are characterized by which one of the following properties moderately low pressure high vapour pressure good conductivity in solid state solubility in polar solvents
14 Some of crystals are good conductors of heat and electricity, they may be ionic in nature of metallic character covalent in nature of molecular nature
15 LiF is a crystalline substance and has ionic crystal metallic crystal covalent crystal molecular crystal
16 One of the following is a ionic solid. Which is that? Fe KBr Diamond Cr
17 An element from the given below exists as discrete small molecules in the solid state. Which is that? Sodium Silicon lodine lron
18 The structure of sodium chloride is simple cube body centered cubic face centered cubic depends upon conditions
19 Which property is associated with ionic solids? Solubility in polar solvents Low melting points Good conductivity in solid state High vapour pressure
20 In crystal of sodium chloride, a Cl-1 ion present at the corner of cube is shared between how many cubes? 8 4 6 10
21 What is the co-ordination number of face centered cubic structure? 12 8 6 10
22 A crystal system in which all three angles and all three edges are different is called triclinic rhombohedral cubic hexagonal
23 Structure of CrO4(-2) is' triclinic cubic octahedral tetrahedral
24 The most unsymmetrical one in crystal system is triclinic Li, Na, K monoclinic hexagonal
25 The hexagonal closed packing is associated with Ag, Cu, Au Zn, Cd, Hg Li, Na, K NaCl, KBr
26 Which impurity makes the shape of NaCl crystal needle like MgSO4 urea glucose MgCO3
27 K2SO4, and K2Cr2O4, are isomorphous solids and exist in cubic form orthorhombic form trigonal form tetragonal
28 The transition temperature of tin is 95.5 C° 13.2 C° 13.2°C 128.5°
29 The existence of an element in more than one form is called allotropy isomorphism polymorphism isotropy
30 The transition temperature of KNO3, is 13.2°C 95.5°C 128°C 32.02°C
31 Polymorphism is shown by AgNO3. Which one of the following options is true for AgNO3? Orthorhombic and rhombohedral Cubic and orthorhombic Cubic and tetragonal Monoclinic and hexagonal
32 Which one is an isomorphic pair? NaNO3, CaCO3, NaF, MgO K2SO4 ,K2Cr2O7 Zn, Cd
33 The examples of a hexagonal system is sugar graphite(a=b not equal to c) {Alpha =beta. not equal to gamma} sulphur diamond
34 In diamond, the carbon atoms are arranged in a tetrahedral manner hexagonal manner square planar manner octahedral manner
35 Hardness of diamond is attributed to the strength of the ionic bonds in the structure three-dimensional network of covalent bonds three-dimensional network of covalent bonds absence of valence electrons in carbon atoms
36 How many allotropic forms are present in carbon? Two Four Three Five
37 Which among the following will show anisotropy? Wood Glass Paper BeCl2
38 Crystals can be classified into 7 crystal systems 4 crystal systems 3 crystal systems 14 crystal systems
39 Glycerine is a polar compound. It boils at 290°C under one atmospheric pressure. It should be distilled under reduced pressure due to reason that there are strong intermolecular forces between molecules of glycerine it decomposes at 290°C low pressure makes the liquid to boil at high temperature <div>the reduced pressure decreases the boiing point of liquids</div>
40 To cook the food at a high mountain is difficult as compared to at sea level. The reason is that: the temperature at the top of the mountain is low the density of water decreases at the mountains the boiling point of water decreases at the mountain the hydrogen bonding in water changes with the change of height
41 CO2 and SO2 are both triatomic molecules, but heat of vaporization of SO2 is greater than that of CO2. This is due to greater electronegative character of sulphur greater size of SO2 molecule SO2 is polar and CO2 is non-polar SO2 is more acidic in nature than CO2
42 The value of the vapour pressure of water at its boiling point at Karachi and Murree is same different depends upon the environmental conditions in both cities greater at Murree and less at Karachi
43 Evaporation occurs at all temperatures and is effected by surface area temperature intermolecular forces all of these
44 What s the boling point of H2O at the peak of Mount Everest? 101 C° 69°C 100 C° 98° C
45 The hydrocarbon with maximum B.P is CH4 C6H14 C4H10 C2H6
46 Point out that which is not an application of liquid crystals? Source of energy In display of electrical devices For skin thermography As temperature sensor
47 Which of the following is not the property of liquid crystal anisotropic isotropic three dimensional arrangement fluidity
48 Cholestryl benzoate tums into milky liquid at 140°C 145°C 148C° 149°C
49 Water may boil at 120 °C when external pressure is: 100 mm of Hg 700 mm of Hg 760 mm of Hg 1489 mm of Hg
50 The B.P of H2O at Murree Hills is 99.8C 98°C 100C° 89°C
51 Amount of heat absorbed when one mole of a solid melts into liquid form at its melting point is called: heat of vaporization latent heat of fusion molar heat of fusion molar heat of sublimation
52 The boiling point of glycerin at 1 atmospheric pressure is: 290°C 390°C 190C° 210°C
53 In order to maintain the boiling point of water at 110 C°, the extemal pressure should be 550 torr between 500 and 760 tor between 760 and 1500 torr any pressure can be maintained
54 Which of following factor affect vapour pressure of a liquid? temperature inter molecules forces size of the molecules all of these
55 The boiling of water may be 120°C, when the external pressure is greater than 760 torr less than 760 torr equal to 760 torr variable
56 Liquids evaporate at every temperature. When the temperature becomes constant for a liquid, then: rate of evaporation is greater than the rate of condensation the rate of condensation is greater than the rate of evaporation The rate of condensation and evaporation become equal it depends upon the nature of the liquid
57 Point out the substance which has maximum vapour pressure at a given temperature? Acetone Water Ethanol Acetic acid
58 Vapour pressure of a substance does not depend upon: physical state of matter temperature intermolecular forces surface area
59 Which of the following liquid has highest bolling point HCI HBr H2O Br2
60 The B.P. of compound is mostly raised by dipole-induced dipole interactions london dispersion forces intramolecular H-bonding intermolecular H-bonding
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