Practise IB Chemistry HL Structure 2 with reviewed questions on bonding, resonance, hybridisation, molecular structure, materials and intermolecular forces.
How does a lithium atom form the most stable ion?
The atom gains a proton to form a positive ion.
The atom loses a proton to form a negative ion.
The atom loses an electron to form a positive ion.
The atom gains an electron to form a negative ion.
Phosphine (IUPAC name phosphane) is a hydride of phosphorus, with the formula .
Draw a Lewis (electron dot) structure of phosphine.
State the hybridization of the phosphorus atom in phosphine.
Outline whether you expect the bonds in phosphine to be polar or non-polar, giving a brief reason.
Phosphine has a much greater molar mass than ammonia. Explain why phosphine has a significantly lower boiling point than ammonia.
Titanium and vanadium are consecutive elements in the first transition metal series.
Describe the bonding in metals.
Suggest why the melting point of vanadium is higher than that of titanium.
Explain why an aluminium-titanium alloy is harder than pure aluminium.
State the type of bonding in potassium chloride which melts at 1043 K .
A chloride of titanium, , melts at 248 K . Suggest why the melting point is so much lower than that of KCl .
Iron may be extracted from iron (II) sulfide, FeS.
Outline why metals, like iron, can conduct electricity.
Iron (II) sulfide, FeS, is ionically bonded.
Describe the bonding in this type of solid.
Suggest why chemists find it convenient to classify bonding into ionic, covalent and metallic.
Explain why the addition of small amounts of carbon to iron makes the metal harder.