Question

To receive credit, you must show your work. STAPLE all pages before submitting your homework. Problems will be selected at random for grading, but a full answer key will be posted to Blackboard. 1 solids, liquids, and solutions, and intermolecular forces. 1. For each pair of substances, identify which has the highest melting point. For each, briefly explain your reasoning. more molecules combine Joneller, so higher the meltins potht b. dispersion s dpole dipole Hydrogon bond dipola Hydrogen bond Mole hydrogen therefore highest milliary Ne: dispersion e. Surface area also matters. More surface area, more contact, stronger cohesion. Your book! mentions this. Based on that, which do you think is most likely to be a solid at room temperature?

Answer 1

97. Da has the highest onelting points as due to the fusion of three rings, it has the nga intermolecular forces. 1.b) city työ nity -77.3 H-bording -182°c o°C weak London +-bonding dispersion forces interofion interaction which is much monet than that of ammonia So, H2O how the highest melting point due to the extensive H-bonding between a water molecules which gives its liquid form a huge internal cohesion 1 1.). O Ne Be -248°C 127°C . Due to the metallic character and huge strength of Metal - Metal (Be-Be) bond, Be- has the highest mp. 1. d) BM2 Ata -7°c 114°C 302°C the size of halogen molecules incheones down the group. Lowrger size leads to greater von der Waals forces of attraction. Hence, ant how the highest mk . - 248.6 °C Iz me period tat-

1.ey. As almeady hinted in the question, more comoing the molecules given surface area means more cohesion. So Y Neopentane Isopontane n-pantane - Neo-pentane how the learst surface area and m-pentone has the most surface area. So, n-pentome will favor liquid state whereas Neo-pent one will toworse solid state atroom temperature as four solids, efficient backing of molecules is the priority and due to the sphenoid shape of reopentane , it facks into esitystalline shape very efficiently