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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).

Acetylene gas is used in welding. Ethylene gas is the precursor to the plastic polyethylene. The gas we call natural gas is primarily methane gas with smaller amounts of ethane gas. Propane gas fires up the backyard barbecue grill. Butane gas is the fuel in lighters. All six of these fuels are compounds that only contain the elements carbon and hydrogen.  Answer the following questions in the corresponding space on the chart below. Use the same format as the examples shown. (6 points total) Acetylene has a carbon-to-hydrogen atom ratio of 1 to 1. What is the carbon-to-hydrogen mass ratio for this compound? (1 point) Ethylene has a carbon-to-hydrogen mass ratio of 6 to 1. What is the carbon-to-hydrogen atom ratio for this compound? (1 point) Ethane has a carbon-to-hydrogen atom ratio of 1 to 3. But one mole of this gas weighs 30 g, not 15 g. What is the molecular formula of ethane? (1 point) Note: Subscripts won’t work; use the format CnHm for CnHm. Methane has a carbon-to-hydrogen mass ratio of 3 to 1 and a molecular weight of 16 g/mol. What is the molecular carbon-to-hydrogen atom ratio for this compound? (1 point) Propane has a carbon-to-hydrogen mass ratio of 9 to 2. One mole of this compound is 46 g/mol.  What is the carbon-to-hydrogen atom ratio for this compound? (1 point) Butane has a carbon-to-hydrogen atom ratio of 2 to 5. What is the carbon-to-hydrogen mass ratio for this compound? (1 point) Compound C-to-H Mass Ratio C-to-H Atom Ratio Molecular Formula Acetylene [acetylene] 1:1 Ethylene 6:1 [ethylene]   Ethane   1:3 [ethane]* Methane 3:1 [methane]   Propane 9:2 [propane]   Butane [butane] 2:5    

A balanced chemical equation can be read in many ways. It shows equal numbers of atoms of each type of element on both the reactants and products side of the equation. This same atom information can be read as moles of each type of element. It also shows the mole ratios of reactants and products, and it expresses the fact that the total mass of the reactants equals the total mass of the products (conservation of mass). Balance the chemical reaction and complete the table for the combustion reaction of methane, the major compound present in natural gas. For this table, you may give your answer as a whole number without units. The computer will make your answer wrong if you include g for grams.  Also, include all coefficients, including 1, in your answers, as Canvas won’t recognize a blank as correct. (Normally answering with proper significant figures and units is the best way to answer.) Balance this equation with the proper coefficients:  [CH4] CH4 + [O2] O2 → [CO2] CO2 + [H2O] H2O  Element Number of atoms in one molecule (not avogadro’s #) Number of moles of C, H, or O Reactant Number of moles in the reaction Mass of compound listed Total Mass in grams of that all Reactants Total mass in grams of all Products C  [AtomsC] 1 CH4  [molesCH4]  16 g  [massReactant] g   H  [AtomsH] 4 O2  [molesO2]  [gO2] g     O  [AtomsO] 4 Products       [massProducts] g       CO2  [molesCO2]  [gCO2] g           H2O  [molesH2O]  [gH2O] g      

These compounds are a good example of what John Dalton called the law of multiple proportions. Briefly explain how the law of multiple proportions led Dalton to the conclusion that matter is composed of particles he termed atoms.