3. how would the following errors affect the concentration of Cl- obtained in question 2b? give your reasoning in each case. a. the student read the molarity of AgNo3 as 0.02104M instead of 0.02014M b. the student was past the endpoint of titration when he took the final buret reading.

8. A student conducts an acid-base titration to investigate the change in pH during a reaction between hydrochloric acid and ammonia solution. a. Name a piece of equipment that could be used to provide an accurate measurement of pH during the titration and explain how it would be calibrated. The student transfers 50cm3 of 1.0moldm3 ammonia solution acid into a beaker. During the titration the student adds 50cm3 1.00moldm³ hydrochloric acid from a burette into the beaker and records the pH throughout. b. Sketch the pH curve produced during this titration.

2. Using the procedure described in this module, a student determined the percent KHP in an impure sample of KHP. A 3.150-g sample of impure KHP required 41.50 mL of 0.1352M NaOH solution for titration. (a) Calculate the number of moles of NaOH required for the titration. (b) Calculate the number of moles of KHP present in the impure sample of KHP. (c) Calculate the number of grams of KHP present in the impure sample. (d) Calculate the percent of KHP in the impure sample, using Equation 8. Equation 8: percent KHP in the impure sample, % = ( mass of KHP in the sample,g/ mass of sample analyzed, g) (100%)

A student titrates 10.0 mL of 2.0 M formic acid, HCO,H (K.= 1.8 x 10-4), using 1.0 M sodium hydroxide, NaOH. 1. What volume of NaOH solution would be needed to reach the equivalence point? a. 10.0 mL b. 20.0 mL c. 30.0 mL d. 40.0 mL

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5 6 7 8 Questions 5-10 refer to the same weak acid/strong base (WA/SB) titration. The K, of hypobromous acid is 2.8 x 10¹⁹. A 30.00 mL solution of 0.300 M hypobromous acid (HBrO) is being titrated with a solution that is 0.600 M in lithium hydroxide (LiOH). What is the initial solution pH (i.e., when 0.00 mL of titrant have been added)? (Two decimal places) Type your answer... Questions 5-10 refer to the same weak acid/strong base (WA/SB) titration. The K, of hypobromous acid is 2.8 x 10¹⁹. A 30.00 mL solution of 0.300 M hypobromous acid (HBrO) is being titrated with a solution that is 0.600 M in lithium hydroxide (LiOH). What volume (in mL) of titrant will have been added at the half-equivalence point? (One decimal place) Type your answer... Questions 5-10 refer to the same weak acid/strong base (WA/SB) titration. The K₂ of hypobromous acid is 2.8 x 10.⁹. A 30.00 mL solution of 0.300 M hypobromous acid (HBrO) is being titrated with a solution that is 0.600 M in lithium hydroxide…

If KI was not available to precipitate AgI from AgNO3 then what reagent can be used instead? HNO3 AgNO3 NH3 HI

At what pH will an aqueous solution of 1.2 M Mg2+ begin to precipitate as Mg(OH)? The Ksp of Mg(OH)2 is 3.6 x 104. O a. 1.8 ОБ. 3.5 OC. 11.2 O d. 12.3 O e. 10.5

Calculate the pH for each point in the titration of 25.0 mL of 0.250 M pyridine, C,H,N(aq), with 0.250 M HBr(aq). pH before the addition of any HBr: pH after the addition of 12.5 mL HBr: pH after the addition of 24.0 mL HBr: pH after the addition of 25.0 mL HBr: pH after the addition of 32.0 mL HBr: