Solutions Review Worksheet

Transcription

1 Solutons Revew Worksheet NOTE: Namng acds s ntroduced on pages and agan on pages You learned ths and were quzzed on t, but snce acd names are n the Data Booklet you wll not be tested on ths on your Fnal Exam. For Chem 30, you wll not be requred to know how to do acd nomenclature. 1. Complete the followng dagram: Matter Pure Substance element heterogeneous mxture or 2. Aqueous solutons are only 1 type of soluton. Gve 2 examples of other types of solutons. 3. When a substance dssolves n water three processes occur. State the processes and ndcate whether each s endothermc or exothermc. Ionc Molecular 4. What determnes whether the complete dssolvng process s endo or exothermc?

2 Chemstry 20 Solutons Revew Worksheet page 2 5. Use your new solublty chart (ncluded here n reduced sze) to decde whether each of the followng onc compounds wll be hgh solublty {form an (aq) soluton} and whch wll be low solublty {reman prmarly n (s) state}. a) Mg(OH) 2 b) MnF 4 c) Sn(ClO 4 ) 2 d) Co(IO 3 ) 2 e) KMnO 4 6. Wrte dssocaton or onzaton equatons for each of the followng n water. Assume each forms an unsaturated soluton unless otherwse ndcated. The new solublty a) NaCl(s) chart wthout the rest of the Data Booklet s b) Fe(CH 3 COO) 3 (s) avalable on my webste. If you ve c) HNO 3 (aq) lost yours, prnt a new one for yourself. d) equaton for formaton of a saturated soluton from CaCO 3 (s) 7. A Chemstry 20 class dd an experment lke the one you dd to determne the solublty of NaCl, except that they used CaCl 2. The followng data were recorded: fnal mass of evaporatng dsh, watch glass, and CaCl 2 (s) g ntal mass of evaporatng dsh and watch glass g room temperature ºc volume of soluton ml Calculate the solublty n g/100 ml. What s the % error f the solublty from the CRC Handbook of Chemstry and Physcs s 74.5 g/100 ml?

3 Chemstry 20 Solutons Revew Worksheet page 3 8. Explan why a pot full of water wll start to develop bubbles along the walls of the pot as t heats up. Ths occurs well before the water begns to bol. What gas s n the bubbles? 9. If you and your frends take a 2 L bottle of pop and drnk ¾ of the pop n t, the next tme you open t the pop wll be nearly flat. What are 2 thngs you could do to stop ths from happenng? 10. A saturated soluton s sad to be n dynamc equlbrum. Explan the meanng of the term n a general sense and then explan why a saturated soluton s a specal case of dynamc equlbrum. 11. Salors on the Frankln expedton to the North Pole n ded from lead posonng. They had hgh lead concentratons n ther body due to consumpton of tnned food n cans soldered wth tn/lead solder. The skeletal remans of 1 salor, havng a weght 10.5 kg, contaned g of lead. What was the concentraton of lead n the bones n ppm, ppb, and % m/m? 12. What s the molar concentraton of glucose n a soluton contanng 4.82 g of glucose n 29.5 ml of soluton?

4 Chemstry 20 Solutons Revew Worksheet page Calculate the molar concentraton of sodum ons n a soluton contanng 2.56 g of sodum carbonate n 500 ml of soluton. 14. A student was nstructed to prepare 125 ml of a mol/l CuSO 4 (aq) soluton. Calculate the mass of solute, CuSO 4 5 H 2 O(s) she would need to prepare the soluton. (Note: when CuSO 4 5 H 2 O(s) dssolves n water you get CuSO 4 (aq).) 15. A dfferent student was gven 1.95 g of KNO 3 (s). He was nstructed to prepare a mol/l soluton of KNO 3 (aq). What volume of soluton could be prepared? 16. Concentrated H 2 SO 4 (l) s approxmately 17.6 mol/l. What volume of concentrated acd would be requred to prepare 200 ml of 1.50 mol/l H 2 SO 4 (aq)? 17. What s one mportant thng to remember when dong the dluton descrbed n queston 15?

5 Chemstry 20 Solutons Revew Worksheet page What s the Arrhenus Theory of acds and bases. (don t worry ts short) 19. Why dd the Arrhenus Theory requre modfcatons? What were the modfcatons? 20. Wrte modfed Arrhenus equatons to explan the acdc behavour of: a) HCl(g) b) SO 2 (g) and the basc behavour of c) NH 3 (g) 21. A weak acd and a strong acd of the same concentratons have very dfferent propertes. The strong acd conducts electrcty better, has a lower ph, and reacts more quckly wth Mg(s). Explan ths theoretcally. 22. It s possble to have a soluton of a strong acd that behaves n a less acdc manner than a soluton of a weak acd. Explan how ths can be accomplshed. 23. Explan the dfference between a polyprotc acd and a monoprotc acd. Gve an example of each.

6 Chemstry 20 Solutons Revew Worksheet page Calculate the ph of a mol/l soluton of HCl(aq). What s poh of the same soluton? 25. What s the ph of a soluton produced by dssolvng 2.75 g of HBr(g) n water to make 700 ml of soluton? 26. A soluton has ph = 3.9. Calculate [H 3 O + ] and [OH ]. 27. A soluton has ph = What s the maxmum ph that can be obtaned by dlutng the soluton? 28. What s the ph of a soluton obtaned by takng 20.0 ml of a soluton of ph = 3.40 and dlutng t to a fnal volume of 125 ml?

7 Chemstry 20 Solutons Revew Worksheet page Separate samples of a soluton of unknown ph produced the followng colours wth the addton of the lsted ndcators. What s the ph of the soluton? ndcator methyl volet orange IV methyl orange bromocresol green soluton colour blue yellow red yellow 30. What two groups of gases are the major contrbutors to acd deposton? 31. Defne or descrbe the followng terms: electrolyte dssocaton solublty hydronum on neutralzaton reacton acd deposton

8 Chemstry 20 Solutons Revew Worksheet page 8 Answers 1. matter pure substance mxture element compound heterogeneous mxture homogeneous mxture or soluton 2. p p p p. 172, solublty chart 6. p , p. 175, p Inv 5.B.1 handout 8. p p p x 10-4 %m/m 1.02 ppm 1.02 x 10 3 ppb mol/l mol/l g L L 18. p p p p p p p p p p p p p throughout I encourage you to fnd the terms and read the background nformaton rather than just lookng n the glossary 17. notes, demonstraton