Question

#4.. please show work and dont skip steps. trying to learn how to do this for the actual biochemistry lab

PART B. PRACTICE CALCULATIONS Convert units (show your work!): a. 0.01 ml b. 0.05 M = MM c. 0.2 M = mM d. 10 mM - M 2. Molar mass of Na olar mass of NaOH is 40 /mol. How many grams of NaOH do you have to take to prepare a. 11 of 10 M solution of NaOH? b. 1L of 10 mM solution of NaOH? c. 100 ml of 10 mM solution of NaOH? 3. Calculate the theoretical pH of 10 mM NaOH using the data below: • NaOH is a strong base, dissociates completely, thus [OH) is equal to (NaOH) • ion product of water [H(OH)=1.0 X 10M2 • pH = -log [H] 4. Calculate the amount of concentrated (37%) HCI in ml necessary to make 100 ml of 10 me solution. HCl is a liquid with molecular weight of 36.5 g/mol. Usually HCl is sold as a solution, and figuring out how to prepare necessary dilutions could be tricky. You can proceed to calculation if you already know how to do it; if not, we will try to do it step by step: a. Calculate the theoretical dry mass in grams of HCl to make 100 ml of 10 mM solution of Ha. as if it was not liquid, but solid. b. Since HC is sold as liquid, we need to measure the amount of stock HCI in ml, not in grams. If the density of HCl solution is 1.27 g/ml, how many ml of liquid 100% HCl do you need to prepare 100 ml of 10 mM solution of HCI? Here you will need to take the amount of grams from the previous step and calculate the amount of ml using the provided density. c. Now, you have to adjust your calculations, since you actually have a 37% HCl solution. This is how HCI is normally sold. You will need to increase the amount of ml you calculated in the previous step accordingly to prepare the solution you need. d. Calculate the theoretical pH of this solution (HCI is a strong acid and dissociates completely 5. Sodium dihydrogen phosphate NaH2PO4 (monobasic) and sodium hydrogen phosphate NazHPO4 (dibasic) are a weak acid and its conjugate base pair that are mixed to make a buffer with pH 7.2 The pka of the acid-base transition below is 7.2: Not:POs ro you NaHPO. HOTO Na" OH HOT o Na Na2HPO. O Na to be on a Mastro

Answer 1

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