Dont forget the units And show work BIUL 134 BIOaogy on ucus

BIUL 134 BIOaogy on ucus ana Macroorgamsms Practice problems on molarity Due beginning of class on Friday, September 18 To do these problems yow will need a Periodic Table. Round oratomic weights. For CL round to the nearest 0.5 Don\'t forget the units! 1. How would you make one liter of a 1 M NaCI solution? 2 How would you make 100 ml of a 1 M NaC1 solution? 3. How would you make 10 Lof a 0.5 M Nacl solution? 4. How would you make 200 ml of a 3 M Naci solution? 5. To protect your cells you need to suspend them in a solution of 0.5 M sucrose (c1aHao,) that also contains o.1 M Nacl. If you want to make 1 L, how would you do it? 6. You dissolve 42.5 g oflithium chloride (Lic) in enough water to make 21iters. What is the concentration (in M? 7. You need to make a lot of2 M calcium chloride (caci2 solution when you go to your stockroom, however, you find you only have 22.2 gleft in the bottle. You decide to use it all and make as much solution as you can while you wait for your order for more Caciz to come in. What volume of water do you add? 8. If there is a 2 M solution of LiCl and you take 50 ml ofit, how many moles of LiCl did you take? How many grams of LiCl did you take? 9. If there is a 1 M solution of HCl and you take 0.5 ml of it, how many moles (or millimoles) of HCI are in that 0.5 ml?

Solution

1).

Mole is a unit of measurement used to express amounts of a chemical substance. The concentration of a solution is mostly expressed by its molarity, which is the number of moles of the dissolved substance per litre of solution.

Molarity = weight/ molecular weight * volume of solution in litres

The molecular weight of NaCl is = 58.44 g.

Thus, to prepare 1 lit of 1 Molar NaCl colution, 58.44 grams of NaCl is to be dissolved in 1 liter of water.