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Answer the following questions using the simplified solubility rules below: Cations that are always soluble: Compounds of group 1 cations (Na+, K+, etc.) and ammonium (NH4+) are always soluble. Anions that are always soluble: Nitrate (NO3−) anions are always soluble. Halides: Compounds of the halides (Cl−, Br−, I−) are soluble except for silver(I) (Ag+) and lead(II) (Pb2+). Sulfate: Compounds of sulfate (SO4 2−) are soluble except for group 2 cations (Ca2+, Sr2+, Ba2+) and lead(II) (Pb2+). Everything else: Most other compounds not listed as soluble in rules 1–4 are assumed to be insoluble.

The boiling point of CH4 is −162 °C and the boiling point of CCl4 is 77 °C. Identify the principal intermolecular forces in each of these compounds and briefly explain the large difference in boiling points. Submit your response using the text editing tools in the box below.

The name of the SO42- ion is ________.

Put the following in order of decreasing metallic character.  Ge, Pb, Rb, Cs, Ni, Ca  

For every gallon of diesel fuel burned, 22.4 lbs of CO2 are produced. In an experiment, if 18.75 lbs of CO2 were collected as a result of burning 1.00 gallon of diesel fuel, what is the percent yield of CO2? Note: Show all work for this question for full credit. Label the question number clearly and circle or highlight all answers. You will upload your work at the end of the exam. The number of significant figures you use in your answer is important. There is an extra 1/2 point available for using the right number of significant figures in your final answer.

The heat energy required to convert a liquid to a gas is known as the heat of vaporization. The heat of vaporization of water is 540 cal/1.00 g or 2.260 kJ/1.00 g. What amount of heat energy is required to convert 25.0 g of water to steam at the boiling point of water? Report your answer in units of kcal (cal). Work out the problem on a separate piece of paper and upload a photo of your response at the end of the test. Please mark the problem clearly and show your work. Enter your answer in the text box below.

Written Work Make sure to show all work for the following questions, labeling each question and answer clearly. You will take one or more pictures of this document to upload at the end of the exam.

The sketch below shows the relative change in energy as two hydrogen (H) atoms are brought closer together. Copy the diagram, then label the point where the bond is most likely to form by inserting two dots to the hydrogens forming the bond, based on Coulomb’s theory. Show all work for this question for full credit. Write out your response on a separate sheet of paper, labeling the question number clearly and circling or highlighting all answers. You will upload a photo of your response at the end of the exam. See the description for details The image shows a graph depicting the relationship between energy (on the y-axis) and distance (on the x-axis). The curve starts from high energy, decreases to a minimum, and then increases again.

Which element is designated by the electron configuration 1s2, 2s2, 2p5?

Coulomb’s Law Explain the following observations and phenomena. Support your answers with what we have learned about the basic force on charged particles. Coulomb’s law: It is all about the amount of charge and the distance between charges—that is, F∝q1q2r2· Be concise and avoid nonessential information (i.e., don’t do a brain dump).