If you think you made a mistake, tick the wrong answer and enter the new answer. Too many protons and neutrons in the atom (C) Too many electrons in the outer shell of the atom. After this time, no air bubbles were observed to be visible in the beaker.
10 A titration was performed by adding NaOH from a Teflon-lined burette to HCl in a Erlenmeyer flask. When analyzing a water sample using the Winkler method, a total of 0.60 moles of thiosulfate was used in the reaction.
In a first-hand study to determine the heat of combustion of ethanol, the determined experimental value differed from the theoretical value. a) Identify a reason for this difference.
Part B (continued)
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Analyze how knowledge of the composition and properties of acids led to changes in the definition of acids. A student conducted a first-hand investigation to identify the relationship between the mass of a metal used in a reaction and the volume of gas produced. In each experiment, 200 ml of hydrochloric acid was added to some zinc, and the volume of gas produced was recorded.
Predict the volume of gas that would be produced in this experiment if 3.00 g of zinc were used. The following procedure was used to determine the mass of calcium carbonate in the tablet. When the reaction between calcium carbonate and hydrochloric acid stopped, the indicator phenolphthalein was added to the reaction mixture.
The phenolphthalein changed from colorless to pink after 14.2 mL of the sodium hydroxide solution was added. a) Write a balanced chemical equation for the reaction that took place between the calcium carbonate in the tablet and the hydrochloric acid. The following data were collected. a) Calculate the percentage of total dissolved solids in the stream sample. Describe a chemical test that could be performed on the water sample to determine the presence of lead.
Sketch on the graph how the concentrations of reactants and product would change after the volume was reduced. ii) Explain the changes shown in your chart. One of the intermediates in the synthesis of sulfuric acid is H2S2O7. (ii) With regard to the properties of sulfuric acid, describe the safety measures necessary for its transport. After equilibrium was reached, 0.0400 mol N2O4(g) was in the vessel. i) Explain the effects of the addition of a catalyst and an increase in pressure on the yield of N2O4 in this reaction when run at 25°C. ii) Calculate the equilibrium constant for this reaction at 25°C and explain any difference from the K value at 100°C.
Discuss this statement by analyzing the changes that have occurred in the industrial methods for producing sodium hydroxide. Describe the chemistry involved in ammonia recovery and suggest a reason why this recovery is desirable. iii) Identify potential environmental issues that may arise from the Solvay process and evaluate methods of addressing those environmental issues. What is the name of these metals? ii) Modern ship hulls contain steels that have lower levels of carbon and sulfur than used in the past.
Discuss this statement by analyzing current methods of corrosion protection for ships. d) An iron cannon was recovered from a wreck on the Great Barrier Reef. The diagram below summarizes some of the steps involved in breathing. i) Compare the energy production of glycolysis with the total energy production of respiration. ii) Explain the role of oxidation and reduction in respiration.
Glycolysis
TCA Cycle
Oxidative phosphorylation
The coach believes that sports drinks will give runners extra energy during both a sprint race and a marathon. Maltodextrin is a polymer made up of many glucose molecules linked together. ii) Describe the chemical process involved when humans store. iii). Use the data in the table to evaluate the hypothesis made by the coach. compound sucrose glucose fructose fructose maltodextrin*.
A solution of iron (II) sulfate is mixed under acidic conditions with a solution of potassium permanganate, resulting in a color change. i). What is the observed color change. ii) Consider the color change in terms of oxidation states. The table gives examples of the colors represented by transition metal complexes. i) Consider the color differences represented by these transition metal complexes. ii) Assess the importance of minerals as pigments to TWO ancient cultures.
Analyze the relationship between first ionization energy and electron configuration using data from the graph. A). The diagram shows the emission spectra of three elements and an unknown mixture. i) Name TWO elements present in the unknown mixture. ii) Describe how emission spectra help identify elements in a mixture. The diagram illustrates the structure of DNA. i) Identify the components labeled X, Y and Z. ii) Explain how the analysis of DNA makes it possible to identify relationships between people. iii) Discuss the ethics of maintaining DNA databases.
A scientist wanted to develop a separation method for a mixture of six carbohydrates using high-performance liquid chromatography. The diagram shows the chromatograms obtained for the mixture using two different solvents as the mobile phase. Describe high-performance liquid chromatography and evaluate the effectiveness of the various solvents used by the scientist to separate the mixture of carbohydrates.
