Description pH Scaling: Acids and Bases Lab Activity Complete the following activity by following the procedure closely. Take notes of observations and questions as you move through the experiment. At the conclusion of your experiment, answer the Analysis questions. Be thorough as you respond to these important questions - your overall Analysis Portion should be three to four pages in length (750-1000 words Part I: Essential Questions 1. What is the pH scale? 2. How are acids and bases measured by a pH indicator? 3. How are acids and bases different? 4. What types of substances are considered acids and bases? Materials: • Copies of Acid/base lab sheets • pH litmus paper (pH testing strips) • Variety of solutions (lemon juice, vinegar, water, tea, milk, soap, baking soda) • Goggles (Safety Precautions) **Students must wear goggles! • Do not taste or directly inhale any of the solutions. Procedure 1. Choose 5 different substances to test. 2. Hypothesize whether each substance is an acid or a base. Record on the table below. 3. Put each substance in a test well. If it is a liquid, test the liquid directly. If it is a solid, it needs to be mixed with water so the pH can be determined. 4. Dip a pH strip into each of the 5 substances and allow it to sit for 10-20 seconds. Using the pH scale on the pH strip container, measure the pH level and record it on the chart. (See attached document) Part II: Data Table: Measurement of pH (See attached document) Name of Substance Hypothesis (is it an acid or a base?) pH Level Acid, base or neutral? Part III: Analysis questions: 1. What does the pH scale indicate? 2. What is an acid? Where are they found on the pH scale? What is a base? Where are they found on the pH scale? 3. Were any substances tested neutral? Why or why not? Explain your answer. 5. Were any of your results surprising? Why or why not? 6. Write five facts you learned about acids and bases. "Make sure to show your work and use the correct amount of significant figures. "
Description Make sure to show your work The rate law for a reaction is found to be rate = k[X]4. By what factor does the rate increase if [X] is doubled? The rate of a hypothetical reaction involving L and M is found to triple when the concentration of L is doubled and to double when the concentration of M is doubled. Write the rate law for this reaction. "Make sure to show your work, and your answers should be provided with the correct amount of significant figures."
Description A classmate states, “All compounds containing H atoms are acids, and all compounds containing OH groups are bases.” Do you agree? Give examples. Will a precipitate form if solutions of barium chloride and sodium sulfate are combined? If so, identify the spectator ions and write the net ionic equation Make sure your response is detailed and written in full sentences.
Description Compare the reactions of CuCl2 with Al shot and Al foil. Discuss some possible reasons for any differences in the reaction of the two forms?
Description Prepare a multi-media presentation to teach a fellow student more about the laws below. Your project will focus on three laws of your choice, so think about which ones you understood best. Choose three from this list: Boyle's Law Charles's Law Gay-Lussac's Law Avogadro's Law Graham's Law The purpose of your presentation will be to explain how to apply these laws. Your target audience should be a fellow student who has some knowledge of chemistry, but needs additional help with these specific laws. For each law that you explain, include the following: History of law (maximum one slide) The formula, and what the formula stands for (maximum one slide) Example Problems: explain how to solve both problems clearly, step by step (use as many slides as you need to clearly illustrate your steps) Each slide should include information as well as a visual aid (picture, video, animated gif, etc). Keep your slides informative but concise. Use problems to illustrate these concepts. Make sure that you are only using your own words. If you use information from the internet or other sources for research, you must cite your sources. Using an online tool such as http://citationmachine.net/index2.php can help you create your works cited page. (Remember that we use APA in Science class.) Grading Excellent Average Poor Clarity Worth: 40% Presentation is easy to follow and informative. Presentation communicates information, but viewer may struggle. Presentation has too much text per slide. Presentation has too little information and cannot stand alone. Accuracy Worth: 40% Math is correct. History is factually accurate. Each variable in the formula is correctly identified. Math includes some errors in computation. There are some historical facts that are inaccurate. Some variables are not correctly identified. Math is not correct. History is not correct. Incorrect formulas were used. Formula is incorrect or lacking variables. Graphics Worth: 20% Presentation includes a variety of appropriate visual aids. Presentation only has one type of graphics. Some graphics are inappropriate or irrelevant. Presentation does not include graphics. "Make sure to show your work and use the correct amount of significant figures. "
Description Click on the following link: https://www.sascurriculumpathways.com/portal/#info/376 username: VirtualLab password:virtualschool2014 complete the virtual lab and then write a lab report in the format of the attached document. Include all necessary data from virtual lab in the report.
Description Question 1 Identify the spectator ions in the reaction Ca(NO3)2 + 2NaCl(aq) ? CaCl2(aq) + 2NaNO3(aq) Select one: a.Na+, NO3- b. Ca+2, NO3- c. Na+, Cl- d. Ca+2, Cl- e. Na+, Cl-, Ca+2, NO3- Question 2 What is the oxidation number of N in NH4+ Select one: a. 4 b. -3 c. -4 d. 1 e. +3 Question 3 What are the spectator ions in the reaction HF(aq) + NaOH(aq) ? NaF(aq) + H2O(l) Select one: a. H+, F- b. Na+, OH- c. Na+, F- d. Na+ alone e. H+, OH- Question 4 What is the oxidation number of S in S2O3-2? Select one: a. -3 b. 2 c. 3 d. 4 e. -2 Question 5 Identify the oxidizing agent in the reaction: Cl2 + 2Br- ? 2Cl- + Br2 Select one: a. Br- b. Cl2 c. Br2 d. Cl- Question 6 What is the molarity of the solution formed by dissolving 10.0g of Ca(NO3)2 in 250 mL aqueous solution? Question 7 Consider the reaction H2SO4(aq) + 2NaOH(aq) ? 2H2O(l) +Na2SO4(aq). If 25 mL of H2SO4 was needed to react with 15 mL of 0.20 M NaOH, what is the molarity of the H2SO4(aq)? Question 8 Which of the following is a weak electrolyte? Select one: a. HF(aq) b. NH4Cl(aq) c. CaCl2(aq) d. CH3OH(aq) e. HCl(aq) Question 9 Identify the reducing agent in the reaction Ca + 2H+? Ca+2 + H2 Select one: a. H2 b. Ca c. Ca+2 d. H+ Question 10 Chromium is less active than Manganese but more active than Cobalt. Which of the following reactions will occur? Select one: a. Co + Cr+3 ? Co+2 + Cr b. Mn + Cr+3 ? Mn+2 + Cr c. Co+2 + Cr+3 ? Co+ Cr d. Co + Cr ? Co+2 + Cr+3 e. Mn + Cr ? Mn+2 + Cr+3 Question 11 Which of the following is a strong electrolyte? Select one: a. HCl(aq) b. NH4Cl(aq) c. CaCl2(aq) d. All of them are e. None of them are Question 12 Identify the spectator ions in the reaction: Ca(NO3)2(aq) + Na2CO3(aq)?CaCO3(s) + 2NaNO3(aq) Select one: a. Na+, NO3- b. Ca+2, CO3-2 c. Ca+2, NO3- d. All are e. Na+, CO3-2 Question 13 Which of the following is a nonelectrolyte Select one: a. CH3OH(aq) b. CaCl2(aq) c. NH4Cl(aq) d. HCl(aq) e. NH3(aq) Question 14 Consider the reaction Mg(OH)2(s) + 2HCl(aq) ? MgCl2(aq) +2H2O(l). What is the mass of Mg(OH)2(s) needed to react with 25 ml of 0.20 M HCl(aq)? Question 15 What is the coefficient of H2O when the following reaction is balanced: Al(OH)3(s) + H2SO4(aq) ?Al2(SO4)3(s) +H2O(l) Question 16 Which of the following will dissociate completely in dilute aqueous solutions? Select one: a. CaCO3(s) b. CO2(g) c. NH4Cl(aq) d. H2O(l) e. HF(aq) Question 17 Complete & Balance the following Reaction: Fe(NO3)3(aq) + Na2S(aq) ? ? + ? Question 18 In which of the following is the oxidation number of the Cl +1? Select one: a. HClO b. HCl c. HClO2 d. HClO3 e. Cl2 Bottom of Form ·Bottom of Form
Description For this assignment, you are to set up the steps and show the work which should equal the answers provided. Unit 3 Lesson 5: Water Apply Vaporization. Make sure that you are showing each step of your work. 1. How much energy is absorbed when 30.3 g of liquid water boils? answer= 68.5kj 2. An energy unit often encountered is the calorie (4.18 J = 1 calorie). Determine the molar enthalpy of fusion of ice in calories per gram. answer = 79.8 cal/g 3. A typical ice cube has a volume of about 16.0 mL. Calculate the amount of energy needed to melt the ice cube. (Density of ice at 0.°C 0.917 g/mL; molar enthalpy of fusion of ice 6.009 kJ/mol;molar mass of H2O 18.02 g/mol.) Determine the mass of the ice cube. answer = 14.7g Determine the number of moles of H2O present in the sample. answer = 0.814 mol Determine the number of kilojoules of energy needed to melt the ice cube. answer = 4.89kj "Make sure to show your work, and your answers should be provided with the correct amount of significant figures."
Description Step 1: Complete this Virtual Lab by interacting with the online Simulation. Answer the Virtual Lab Questions in complete sentences to demonstrate your learning. Step 2: Submit your answers in a word document. Step 3: **Prepare Lab Report according to outline in attached document( Look at lab outline, it is not that intensive) http://www.glencoe.com/sites/common_assets/science/virtual_labs/E17/E17.swf
