Question

1. Use the following chart of boiling and melting point temperatures to answer the following questions. Notice that the melting and boiling points can be grouped into two categories: those that occur at relatively low temperatures and those that occur at relatively high temperatures. Elemental form Melting point Boiling point Name H2 He 13.81 KL 0.95 K 20.28 K 4.22 K | hydrogen helium L i(s) 453.65 K 1615 K lithium Be(s) 1560 K 2744 K beryllium B(s) 2348 K 4273 K boron C(s) 3823 K 4098 K carbon N2 O 2 | 63.15 K | 54.36 K 77.36 K 90.20 K nitrogen oxygen F2 53.53 K 85.03 K fluorine Ne 24.56 K 27.07 K neon a. List the elemental forms that have relatively low melting and boiling points. Identify if the element is a metal or a nonmetal. b. What type of bonding and/or interactions (LDFs, metallic bonding, covalent bonding) might be overcome during a phase change for each of the elemental forms you listed in part a? c. List the elemental forms that have relatively high melting and boiling points. Identify if the element is a metal or a nonmetal. d. What type of bonding and/or interactions (LDFs, metallic bonding, covalent bonding) might be overcome during a phase change for each of the elemental forms you listed in part c?

Answer 1

1(a.) Out of the given elements, Low melting and boiling point temperature is of Helium. (He)

Helium is a non-metal.

1(b.) As helium is a non metal. The only interactive forces between the helium atoms present is London Depersion forces. Thus London Despersion forces have to overcome during a phase change.

1(c.) Relatively high melting point is of Carbon (C)

and relatively high boiling point is of Boron (B).

both boron and Carbon are non-metals.

1(d.) The only forces of interaction present in these non-metals in the elemental state are London Despersion forces. Thus London Despersion forces are need to overcome to change the phase.