10.50. What hybrid orbitals would be expected for the central atom in each of the following molecules or ions? a. PCl3 b. SiCl4 c. BeF2 d. SO2 10.52. a. Nitrogen trifluoride, NF3, is a relatively unreactive, colorless gas. How would you describe the bonding in the NF3 molecule in terms of valence bond theory? Use hybrid orbitals. b. Silicon tetrafluoride, SiF4 ‍, is a colorless gas formed when hydrofluoric acid attacks silica (SiO2)‍ or glass. Describe the bonding in the ‍ SiF4 molecule, using valence bond theory. 10.57. Describe the electronic structure of each of the following, using molecular orbital theory. Calculate the bond order of each and decide whether it should be stable. For each, state whether the substance is diamagnetic or paramagnetic. a. Be2 b. He2+ c. N2- 10.58. Use molecular orbital theory to describe the bonding in the following. For each one, find the bond order and decide whether it is stable. Is the substance diamagnetic or paramagnetic? a. C2+ b. Be2+ c. Ne2

For a family dinner, jose’s mom baked a loaf of bread. during the meal, his grandmother commented, “this bread is so dense! ” what do you think his grandmother meant by the word dense? you have some ideas regarding density already, but this experiment will enrich your understanding of the relationship between mass, volume and the density of objects. when making measurements in this experiment we will be using si units, the international system of units. the purpose of using si units is to have the ability to communicate and compare data results with other experiments without having to make conversions. measurement symbol si unit length m meter mass kg kilogram volume l liters density kg/l kilograms per liter any calculations that are performed during this experiment will ultimately be reported in scientific notation. recall that scientific notation is extremely important when we have data that is extremely small or large. scientists rely on a standard form of communication to quickly make hypotheses and judgements based on data. what is the density of block a? a0kg/l what is the density of block b? a1kg/l what is the density of block c? a2kg/l what is the density of block d? a3kg/l what is the density of block e? a4kg/l which block is the densest? a5