Chem119-935am-quiz9-key

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A student weights out 3 samples of KHP to standardize a NaOH solution and added 100 mL to each flask. They ran out of time and placed the flasks in the storage cabinet for the week. The following week the flasks only contained 85 mL of solution. What should the student do? O a) Add 15 mL of water and continue. KHP does not evaporate. b) Start over. Some of the acid evaporated O c) Decrease the volume in the burette by 15 mL as well. d) Add more indicator to account for the decreased volume.

What volume in L of a 0.32M Mg(NO:)2 solution contains 45 g of Mg(NO:): ? X STARTING AMOUNT ADD FACTOR ANSWER RESET *( ) 148.33 86.32 10 45 1 210.34 6.022 x 1023 0.097 0.95 0.32 140 0.30 L mL mol Mg(NOs): M Mg(NOs): g Mg(NOs)2 g Mg(NO:)»/mol

Please answer Parts 2 and 3

Hi! Can you help me with these?  Assignment: Balance these problems and find the percentage of it. Show your solution. (kindly refer to the picture on how must the solution look like)  2. Al(OH)3 + HC2H3O2 -----------> Al(C2H3O2)3 + H2O

Part 1 – Preparation of CaCO3(s)  The following is a procedure that was theoretically performed by a student. Read through the procedure and answer the questions below. A 10.0 mL graduated cylinder to measure 10.0 mL of a 1.00 M CaCl2 solution into an initially empty 50.0 mL beaker. A 50.0 mL graduated cylinder was then used to measure out 25.0 mL of 0.500 M K2CO3. This K2CO3 solution was then added to the beaker containing the CaCl2 The solution became cloudy, and the student concluded that a precipitate must have formed. Write a balanced chemical reaction below, including phases, and identify the chemical formula of the precipitate:   Answer the questions below as part of Data Analysis.  1. What is the actual yield of the product? 2. Using stoichiometry, calculate the limiting reactant, and the theoretical yield (the mass of CaCO3 product) for the reaction. 3. Determine the percent yield of the reaction.

3. A tank contains a 200 liters of fresh water. Brine containing 2.5 N/liter of dissolved salt runs into the tank at the rate of 8 liters/min and the mixture kept uniform by stirring runs out at 4 liters/minute. Find the amount of salt when the tank contains 240 liters of brine. The concentration of the salt in the tank after 25 minutes’ amounts to how much?

13. A 800.0 L sample of drinking water is found to contain 2.00 mg of arsenic. What is the concentration (in M) of arsenic in the sample? A: 3.34 x 10-8

I have 6 tubes with the contents labeled. How can I make a 20% concentration serial dilution? Please show the steps and the final dilutions for the tubes as a fraction.

To what volume (in mL) should 0.67 mL of an 5.21 M acetic acid solution be diluted in order to obtain a final solution that is 1.77 M? Calculate to 2 decimal places Read about significant figures and rounding in the Helpful Resources page! Do not include units when reporting your answer Use standard notation or scientific notation as accepted by blackboard e.g. 0.001 or 1E-3, not 1 x 10^-3

AaBbCcDc AaBbCcDc AaBbCC AABBCCC A aB 前。 1 Normal 1 No Spac... Heading 1 Heading 2 Title Paragraph A sample of potassium bicarbonate (KHCO3) was reacted with HCl to produce KCl. The following Styles 7 data was collected. Mass of beaker 28.43 g Mass of beaker + KHCO3 36.95 g Volume of HC1 12.0 mL Concentration of HCl 9.0 M Mass of beaker +residue (KCI) 33.82 g Calculate the following quantities. Show calculations where requested: Mass of KHCO3 Mass of residue Mass of 1 mol of KHCO3 No. of moles of KHCO3 used Show calculations below No. of moles of HCl added Show calculations below: Assuming KHCO3 is the limiting reactant, how many grams of KCl can be formed? Show calculations below: Assuming HCl is the limitingʻreactant, how many grams of KCl can be formed? Show calculations below: Which reactant is limiting? Which reactant is excess? Actual yield of KCI: Theoretical yield of KCl: Percent yield of KCl: W

how did you get the dilution factor? is the dilution factor 9? or 91?

IV. Data Collection Original NaOH Stock solution concentration (M): 10.0 NM Volume of stock used (mL): 20.000ML Total volume of solution in flask after dilution (mL): 100.000ML New NaOH solution concentration (Working Stock) (M): 2.0M Hint: Label out what each molarity and volume above is, and then calculate the New NAOH solution concentration using M1V1 = M2V2 Table 1. Raw titration data Trial 1 50.000 M L 24.500mし 23.500ML Trial 2 Trial 3 33.000ML 9,500ML Initial Buret Reading Final Buret Reading Volume of NaOH (aq) used Molarity of NaOH (aq) used Volume of HCI (aq) used Color at equivalence point 24.500ML 3.000 ml 23.500ML 23.500 mL 20.0 ML 20.0 ML Pink 20.0ML pink pink Table 2. Calculated equivalence amounts and molarity of HCI Trial 1 Trial 2 Trial 3 Moles of NaOH used in titration Moles of HCI neutralized in unknown sample Molarity of HC Average Molarity Show all calculations here: M,V, = Mz Vz = 2.0M (10.0M) (20.000 g)= uk (100. 00ome)= 100ML 100 A (2.0m) (100.000mi) = UK…

com/alekscgi/x/Isl.exe/1o_u-IgNslkr/J8P3JH-IBEWe Maps O MEASUREMENT Lindsay Adding or subtracting and multiplying or dividing measurements chemistry student must write down in her lab notebook the concentration of a solution of sodium hydroxide. The concentration of a solution equals the mass what's dissolved divided by the total volume of the solution. re's how the student prepared the solution: • The label on the graduated cylinder says: empty weight: 6.050 g dlo - She put some solid sodium hydroxide into the graduated cylinder and weighed it. With the sodium hydroxide added, the cylinder weighed 96.4 g. - She added water to the graduated cylinder and dissolved the sodium hydroxide completely. Then she read the total volume of the solution from the markings on the graduated cylinder. The total volume of the solution was 151.66 mL. Ar at concentration should the student write down in her lab notebook? Be sure your answer has the correct number of significant digits. -1 gmL

A student takes a sample of KOH solution and dilutes it to 100.00 mL of water. The student determines that the diluted solution is 0.024 M KOH, but has forgotten to record the volume of the original sample. The concentration of the original solution is 3.685 M. What was the volume of the original sample (in mL)? Answer to 2 decimal places Read about significant figures and rounding in the Helpful Resources page! Do not include units when reporting your answer Use standard notation or scientific notation as accepted by blackboard e.g. 0.001 or 1E-3, not 1 x 10^-3

Chem101 -> A neutral solution of water at a particular temperature has a concentration of OH- of 7.5 x 10-7 M. What is Kw at this temperature? CHEM 101 0pp dd

Equal volumes of Solutions 2 and 3 were mixed in the lab. Suggest a measurement that could be made in the lab to provide evidence that a chemical reaction occurred when Solutions 2 and 3 were mixed.

10. Concentrated nitric acid, HNO3(aq), has a concentration of 15.7 M. What volume of concentrated nitric acid miust be diluted to make 275 mL of 0.130 M nitric acid solution? Multiple Choice 0.828 mL 15.7 mL 2.28 mL 8.28 mL 0.228 mL

A solution contains 38% phosphoric acid by mass. This means that ________. A. the density of this solution is 3.8 g/mL B. 1 L of this solution contains 38 mL of phosphoric acid C. 1 mL of this solution contains 38 g of phosphoric acid D. 1 L of this solution has a mass of 38 g E. 100 g of this solution contains 38 g of phosphoric acid

< STARTING AMOUNT X A brine solution is 3.50% NaCl by mass. Given that its density is 1.071 g/mL , determine the quantity of liters of solution that contains 5.00 moles of NaCl 5.00 ADD FACTOR 0.1 *( ) 3.50 10 35.45 Question 29 of 33 1.071 0.01 8.03 x 1022 1000 100 ANSWER 7.80 22.99 0.0156 L solution g NaCl/mL g solution mL solution kg solution g NaCl/g solution 58.44 6.022 x 1023 0.0780 moles of NaCl mol NaCl RESET 0.001 2 1 g NaCl 1.56

In lab this week, assume you use a 25.00-ml volumetric pipet to transfer the standard red dye solution having a concentration of 4.521 x 104 M to a 100.00-mL volumetric flask. This solution is called your "Stock Solution" and has a concentration of: O a. 9.042 x 105M O b. 1.507 x 104 M Ос 2261 х104 м O d. 1.130 x 104 M

Sample 1 Sample 2 Sample 3 Mass of Erlenmeyer Flask (g) 24.33 24.37 24.44 Mass of Erlenmeyer Flask + Calcium Hydroxide Solution (g)   (g)(lime water) 27.22 27.29 27.33 Mass of Calcium Hydroxide Solution (g) 2.89 2.92 2.89 Volume of Ca(OH)2 Density = 1.000 g/mL 2.89 2.92 2.89 Concentration of HCl (M) 0.1 0.1 0.1 Initial HCl Volume in Syringe (mL) 1.00+1.00 1.00+1.00 1.00+1.00 Final HCl Volume in Syringe (mL) .72 .66 .54 Volume of HCl Delivered (mL) 1.28 1.34 1.46 Moles of HCl Delivered       Moles of OH- in Sample       Moles of Ca2+ in Sample       Molar Solubility (M)       Calculated Ksp       Average Calculated Ksp         Hello, I need to know how to actually solve each one because I will need to show my work.

Sample 1 Sample 2 Sample 3 Mass of Erlenmeyer Flask (g) 24.33 24.37 24.44 Mass of Erlenmeyer Flask + Calcium Hydroxide Solution (g)   (g)(lime water) 27.22 27.29 27.33 Mass of Calcium Hydroxide Solution (g) 2.89 2.92 2.89 Volume of Ca(OH)2 Density = 1.000 g/mL 2.89 2.92 2.89 Concentration of HCl (M) 0.1 0.1 0.1 Initial HCl Volume in Syringe (mL) 1.00+1.00 1.00+1.00 1.00+1.00 Final HCl Volume in Syringe (mL) .72 .66 .54 Volume of HCl Delivered (mL) 1.28 1.34 1.46 Moles of HCl Delivered       Moles of OH- in Sample       Moles of Ca2+ in Sample       Molar Solubility (M)       Calculated Ksp       Average Calculated Ksp       I am very confused how to solve the blank spots in the table. Everything including and after "Moles of HCl Delivered" confuses me. Please help me figure out how to solve the sections correctly. Also feel free to…

35) A solution has a density of 1.22 g/mL. What volume of the solution has a mass of 48.2 g?. A) 39.5 mL B) 49.4 mL C) 1.22 mL D) 58.8 mL 3 E) 0.00253 mL

please answer the questions with explanation/solution based from the choices A-E. please type the solution thank you