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The graph shows the distribution of molecular speeds for four different gases at the same temperature. What property of the different gases can be correctly ranked using information from the graph, and why? The figure presents a graph of 4 curves with horizontal axis labeled Molecular Speed, in meters per second, and vertical axis labeled Number of Molecules. The first curve is a bolded line that begins near the origin and moves drastically upward and to the right, reaching its peak roughly 10% across the horizontal axis and 95% up the vertical axis, then moves drastically downward and to the right, reaching the lowest point at roughly 25% across the horizontal access, after which it moves horizontally to the right until reaching the rightmost point on the vertical axis. The second curve is a nonbolded line that begins near the origin and moves very steeply upward and to the right, reaching its peak roughly 20% across the horizontal axis and 50% up the vertical axis, then moves very steeply downward and to the right, reaching the lowest point at roughly 30% across the horizontal access, after which it moves horizontally to the right until reaching the rightmost point on the vertical axis. The third curve is a dashed line that begins at the origin and moves steeply upward and to the right, reaching its peak roughly 30% across the horizontal axis and 30% up the vertical axis, then moves steeply downward and to the right, reaching the lowest point approximately 50% across the vertical axis and moving horizontally until reaching the rightmost point on the horizontal axis. The fourth curve is a dotted line that begins near the origin and gradually moves upward and to the right, reaching its maximum point halfway across the horizontal axis and roughly 25% up the vertical axis, before gradually moving downward and to the right, ending at the rightmost part of the horizontal axis and at the lowest point on the vertical axis.

Answer the questions about the following pairs of compounds: Consider the two isomers of C3H6O, labeled substance A and substance B. Which one do you expect to have a higher boiling point? Explain. Substance A has a central carbon atom that is double bonded to an oxygen atom and single bonded to two methan, CH3, groups. Substance B has a two central carbon atoms double bonded to each other. The central carbon on the left is single bonded to a hydrogen atom and an OH group. The central carbon on the right is bonded to a hydrogen atom and a methane, CH3, group. Consider the following two hydrocarbons. Which do you expect to have a lower vapor pressure? Explain. The first hydrocarbon is labeled Octane, with the formula C8H18. The figure shows a linear molecule with 8 single bonded carbon atoms surrounded by 18 single bonded hydrogen atoms. The second hydrocarbon is labeled Nonane, with the formula C9H20. The figure shows a linear molecule with 9 single bonded carbon atoms surrounded by 20 single bonded hydrogen atoms.

The reaction represented below goes essentially to completion. The reaction takes place in a rigid, insulated vessel that is initially at 600 K   CH3OH(g) → CO(g) + 2 H2(g) ΔH° = +91 kJ/molrxn   A sample of CH3OH(g) is placed in the previously evacuated vessel with a pressure of P1 at 600 K. What is the final pressure in the vessel after the reaction is complete and the contents of the vessel are returned to 600 K?

Using a spectrophotometer, a student measures the absorbance of four solutions of CuSo4 at a given wavelength. The collected data is given in the table below. Which of the following is the most likely explanation for the discrepant data in trial 4? Trial[Cu2+]Absorbance10.0250.12420.0500.26830.1000.52040.1500.680

Gases generated in a chemical reaction are sometimes collected by the displacement of water, as shown below. Which of the following gases can be quantitatively collected by this method? A diagram shows gas being released through a pipe into a graduated tube, standing inverted in water collected in a beaker. The water level in the tube is higher than that of the water level in the beaker. The space above the water level in the tube is labeled, collected gas.

A mixture containing equal numbers of moles of ethyl acetate and butyl acetate was separated using distillation. Based on the diagrams shown below, which of the following identifies the substance that would be initially present in higher concentration in the distillate and correctly explains why that occurs?   The figure shows a molecule labeled Ethyl Acetate. There are a total of 4 C atoms, 8 H atoms, and 2 O atoms in the molecule. Starting at the left of the figure, there are 3 H atoms each connected with a single bond to a C atom, which is connected with a single bond to a second C atom to the right. An O atom is connected with a double bond above the second C atom, and the second O atom is connected with a single bond to the right side of the second C atom. Each O atom has 2 pairs of nonbonding electrons. The single-bonded O atom is connected with a single bond to another C atom to the right. 2 H atoms are connected with single bonds to the third C atom, which is connected with a single bond to the last C atom to the right. There are 3 H atoms each connected with a single bond to the last C atom. The figure shows a molecule labeled Butyl Acetate. There are a total of 6 C atoms, 12 H atoms, and 2 O atoms in the molecule. Starting at the left of the figure, there are 3 H atoms each connected with a single bond to a C atom, which is connected with a single bond to another C atom on the right. An O atom is connected with a double bond above the second C atom, and the second O atom is connected with a single bond to the right side of the second C atom. Each O atom has 2 pairs of nonbonding electrons. The single-bonded O atom is connected with a single bond to a chain of 4 C atoms single bonded to each other. The first 3 C atoms in the chain each have two H atoms, each connected with a single bond. The fourth C atom in the chain has 3 H atoms, each connected with a single bond.

Beaker X and Beaker Y each contain 1.0 L of solution, as shown. A student combines the solutions by pouring them into a larger, previously empty Beaker Z and observes the formation of a white precipitate. Assuming that volumes are additive, which of the following sets of solutions could be represented by the diagram above? A diagram shows the combining of two solutions collected in two 1 liter beakers. The beaker X contains A g N O 3, (aqueous). The vessel has A g plus and N O 3 minus ions. Plus. The beaker Y contains M g C l 2 (aqueous). The vessel has M g minus and C l 2 plus ions. The resultant combination of the solutions is collected in a bigger beaker Z. The beaker is titled, A g C l (solid), and M g begin parenthesis N O 3 end parenthesis subscript 2, (aqueous). Precipitate in the beaker is labeled, Solid A g C l.

A 1.0 L sample of a pure gas is found to have a lower pressure than that predicted by the ideal gas law. The best explanation for the observation is that the molecule of the gas

Using the absorbance and concentration values for the five standard solutions, prepare a graph of the absorbance (y) versus the concentration (x) values. Draw a best-fit straight line for your data and calculate the slope and y-intercept for Beer’s plot. Then determine the concentration of your unknown brass solution. 

In this lab, you will place a piece of brass into nitric acid. Copper and zinc both react with nitric acid separately. Copper reacts with nitric acid to make copper (II) nitrate, as well as some gaseous nitrogen oxides, brown gasses which will evolve out of the beaker, one of the main reasons this reaction must be performed in a fume hood. Zinc reacts with nitric acid to form zinc nitrate as well as nitrogen oxides. The resulting solution is bright blue. Brass is usually just copper and zinc, though sometimes there are other metals present. Based on your investigation in #1, identify which ion, Cu2+, SO42-, NO31-, Zn2+, or Fe3+, is responsible for the blue color.