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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.

Different regions, or blocks, of the periodic table correlate with the electron capacity of s, p, d, and f orbitals. These regions have been sketched on the periodic table below. For each region, enter the type of orbital correlated with it. (Enter only the letter.) [i] [ii] [iii] [iv] See the description for details The image shows a diagram with four labeled regions: I, II, III, and IV. The diagram appears to represent sections of a larger structure, with each labeled region depicted as a separate area within the design.      

Which monoclonal antibody is used to treat Crohn’s disease?

Which cell type is the most important for killing tumor cells?

We often see depictions of the atom like the one shown below on this old Boy Scout Atomic Energy merit badge. Identify the following statements describing the badge as either correct or incorrect as compared to our current understanding, or model, of the atom. See the description for details The image shows a Boy Scout Atomic Energy merit badge with an embroidered design featuring an atom. The atom is depicted with a central nucleus and electron paths that resemble the Bohr model, with electrons represented as dots orbiting around the nucleus. The badge is outlined in green with a yellow background. List the following items as either correct or incorrect.

Which drug inhibits mTOR?

What type of antibody treatment is Pembrolizumab (Keytruda)?