CHEMISTRY DEPARTMENT WAID ACADEMY BONDING AND PROPERTIES

Which of the following chlorides is likely to have the least ionic character? 1.CsCl. 2.CaCl 2. 3.LiCl. 4.BeCl 2. 30

Which type of structure is found in a substance melting at 811 o C which conducts electricity when molten, but not when solid? 1.Covalent molecular. 2.Covalent network. 3.Ionic. 4.Metallic. 20

In which of the substances, in the solid state, would van der Waal's forces be a significant "intermolecular force"? 1.Sodium chloride. 2.Carbon dioxide. 3.Magnesium. 4.Ice. 20

The melting point of the group 7 elements increase on descending the group because the 1.covalent bond lengths increase. 2.electronegativity values decrease. 3.van der Waal's attractions increase. 4.nuclear charges increase. 20

Tetrachloromethane, CCl 4, is considered to be a non-polar substance because 1.the polar bonds are arranged symmetrically. 2.the C-Cl bonds are non- polar. 3.a covalent network structure exists. 4.only linear molecules are polar. 20

In which of the following molecules does hydrogen bonding exist? 1.CH 4. 2.PH 3. 3.H 2 S. 4.NH 3. 20

Graphite, a form of carbon, conducts electricity because it has 1.metallic bonding. 2.van der Waal's forces. 3.delocalised electrons. 4.pure covalent bonding. 20

Which type of bonding can be described as intermolecular? 1.Hydrogen. 2.Covalent. 3.Metallic. 4.Ionic. 15

Which oxide would be a solid at room temperature (20 o C) and a gas at 325 o C? You may wish to refer to the data booklet. 1.Fluorine oxide. 2.Phosphorus oxide. 3.Magnesium oxide. 4.Boron oxide. 20

Which of the substances shown below is covalent molecular? 1.Carbon (graphite). 2.Carbon (fullerine). 3.Carbon (diamond). 4.Silicon. 15