3. While determining the volume during this experiment (Part II), if the total volume of the flask were incorrectly reported as 125 mL, how would this error affect the calculated molar mass of the unknown volatile liquid? Explain.

A student finds that they have 0.2545 g of NH4Cl, 1.1502 g of NaCl, and 1.0181 g of SiO2. Calculate the percent gained or lost during this experiment if the initial mass of the mixture was 2.5537 g.

For experiment of PREPARATION OF ACETYLSALICYLIC ACID (ASPIRIN): The experiment required 3 drops of concentrated sulfuric acid. Why was this acid added? Would the reaction take place if this reagent were omitted? A student thought he carefully followed the directions in the experimental procedure, and he expected 2.63 g of product. However, his isolated product weighed 3.05 g. What would account for the excess weight? Bottles containing old aspirin tablets often smell of vinegar. The presence of what chemical causes this smell? How does this chemical form?

1. Develop a detailed separation scheme for the separation and determination of the percent composition of your sample which will be a mixture of NaCl, NH.CL, and sand. You are expected to use the properties of the components listed below and some of the techniques listed in the table in the pre-lab queries (and used in Separations I). Keep in mind that any chemistry student should be able to pick up your scheme, understand it, and use it to complete the separation and calculation of % composition. Place the scheme on a separate sheet of paper. Component Solubility (@25°C) Melting Point Hardness sodium chloride, NaCl 35 g/100 mL water 801°C soft ammonium chloride, NH&Cl 37 g/100 mL water sublimes 350°C soft sand, SIQ2 insoluble 1600°C hard Example of compounds in a container. Naci NH.CI sio2 Exploring the Chemical World, PGCC, 2003 4 RESULTS Show all calculations with units in this space.

When answering this problem, report the answer with the appropriate number of significant figures. When entering units, use proper abbreviated units with proper capitalization. A titration is performed to determine the amount of sulfuric acid, H2SO4, in a 6.5 mL sample taken from car battery. About 50 mL of water is added to the sample, and then it is titrated with 43.37 mL of a standard 0.5824 molar NaOH solution. You balanced this reaction in a previous problem. How many moles of sulfuric acid are present in the original sample? Note: Your answer is assumed to be reduced to the highest power possible. Your Answer: ______x10 ____power_____units

Here is a graph of the molarity of acetonitrile CH3CN in a reaction vessel during a certain chemical reaction. Use this graph to answer the questions in the table below

Based on this. What was the percentage by mass of water in the sample?

Tell whether each of the following errors will cause the experimental mass percent of the sodium bicarbonate to be higher than, lower than, or the same as the true value. Explain your answer. The crucible was not heated long enough prior to adding mixture. Some of the carbonate spattered out from the crucible during heating The sample was not heated to constant mass. The mass of mixture used is greater than the recommended mass.

How much 20.0% NaOH should I put in a 30.0 ml tube if my dilution ratio is 1/10. What is the concentration of the tube. ml of 20.0% Just put the number of mL Do not enter anything but a number. Use correct sig figs. Remember ratios and conversion factors do not enter the significant figure calculation. What is the concentration in percent. Again, correct significant figures. NUMBERS only not the % sign

When answering this problem, report the answer with the appropriate number of significant figures. When entering units, use proper abbreviated units with proper capitalization. A titration is performed to determine the amount of sulfuric acid, H2SO4, in a 6.5 mL sample taken from car battery. About 50 mL of water is added to the sample, and then it is titrated with 43.37 mL of a standard 0.5824 molar NaOH solution. You balanced this reaction in a previous problem.How what is the molar concentration of sulfuric acid in the original sample? Present the answer in the following form. Answer: _____ x10 ___power ___units