http://zh.sgforums.com/forums/2297/topics/304897 zh-CN 60 <p>write the ionic eqn:<br /> <br /> Cu^2+ + 2I^- &gt; Cu + I2<br /> <br /> 22.5/1000*0.1080 = 0.00243<br /> <br /> 0.00243/2 = 0.001215<br /> <br /> 0.001215/25*1000=0.0486 mol/dm3<br /> <br /> mr = 54+32+64+90=240<br /> <br /> 240*0.0486 = 11.7g/dm3<br /> <br /> not very sure...<br /></p> Thu, 24 Jan 2008 22:39:08 +0800 zh.sgforums.com:2297:304897:7802346 starmoonsun http://zh.sgforums.com/forums/2297/topics/304897 <p>opps sorry, i forgot to put down, oh there’s no answer given to me leh..</p> Thu, 24 Jan 2008 22:32:39 +0800 zh.sgforums.com:2297:304897:7802307 limywv http://zh.sgforums.com/forums/2297/topics/304897 <p>you haven’t reply got answer a not… Guideline is, please put answer if there is. It would be polite to state so too if there’s no answer</p> Thu, 24 Jan 2008 22:24:05 +0800 zh.sgforums.com:2297:304897:7802247 eagle http://zh.sgforums.com/forums/2297/topics/304897 <p>sorry it’s CuSO4.5H2O</p> Thu, 24 Jan 2008 22:05:47 +0800 zh.sgforums.com:2297:304897:7802116 limywv http://zh.sgforums.com/forums/2297/topics/304897 <p>got answer a not<br /> <br /> Is it CuSO3.5H2O or CuSO4.5H2O?</p> Thu, 24 Jan 2008 21:17:36 +0800 zh.sgforums.com:2297:304897:7801831 eagle http://zh.sgforums.com/forums/2297/topics/304897 <p>Hey guys i've a question to ask...ok here it is:<br /> <br /> 25 cm³ of a copper (II) sulphate solution was added to 30cm³ of potassium iodide solution which was in excess.<br /> <br /> the iodine liberated was titrated with 22,5 cm³ of 0,1080 mol dm^-3 sodium thiosulphate solution. what was the mass in grams of the pentahdydrate, CuSO4.5H2O per dm³ of the solution?<br /> <br /> guys thanks..<br /> <br /> -- edited to change from CuSO3.5H2O to CuSO4.5H2O</p> Thu, 24 Jan 2008 20:54:05 +0800 zh.sgforums.com:2297:304897:7802318 limywv http://zh.sgforums.com/forums/2297/topics/304897