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Pls I Need Any Chemistry Guru Help / Industrial Chemistry Vs Chemical Engineering / "Ababio" Chemistry Textbook - Osei Yaw Ababio (2) (3) (4)
Chemistry Guru's Help Out. by zhukafa(m): 7:12am On Nov 21, 2013 |
A sample of 0.500g of impure CaC03 was dissolved in 50.0cm³ of 0.100moldm–³ HCL and the remaining acid was titrated against 5.0cm³ of 0.12mol dm–³ NaOH solution. find the percentage of CaCO3 in the sample. |
Re: Chemistry Guru's Help Out. by immortalcrown(m): 7:16am On Nov 21, 2013 |
Really? |
Re: Chemistry Guru's Help Out. by zhukafa(m): 10:24am On Nov 21, 2013 |
[quote author=immortalcrown]Really?[/quoteese] yes bro, if you can help out, I appreciate. |
Re: Chemistry Guru's Help Out. by Odilop: 3:29pm On Nov 21, 2013 |
zhukafa: A sample of 0.500g of impure CaC03 was dissolved in 50.0cm³ of 0.100moldm–³ HCL and the remaining acid was titrated against 5.0cm³ of 0.12mol dm–³ NaOH solution. find the percentage of CaCO3 in the sample.typing... |
Re: Chemistry Guru's Help Out. by valdprof: 3:33pm On Nov 21, 2013 |
zhukafa: A sample of 0.500g of impure CaC03 was dissolved in 50.0cm³ of 0.100moldm–³ HCL and the remaining acid was titrated against 5.0cm³ of 0.12mol dm–³ NaOH solution. find the percentage of CaCO3 in the sample.pls wat do we call chem reactions dat release energy to the environment ..pls |
Re: Chemistry Guru's Help Out. by Odilop: 3:41pm On Nov 21, 2013 |
valdprof: pls wat do we call chem reactions dat release energy to the environment ..plsexothermic or exergonic reaction |
Re: Chemistry Guru's Help Out. by Odilop: 3:51pm On Nov 21, 2013 |
zhukafa: A sample of 0.500g of impure CaC03 was dissolved in 50.0cm³ of 0.100moldm–³ HCL and the remaining acid was titrated against 5.0cm³ of 0.12mol dm–³ NaOH solution. find the percentage of CaCO3 in the sample.Mole of acid used is. 50/1000*0.1 =0.005moles No of mole of caco3 2HCL+CaCO3=CO2+CaCL2+H2O 2 mole of HCL=1 moles of CaCO3 0.005mole give 0.005/2 mole of CaCO3 0.0025 moles of cacO3 Mass of caCO3=0.0025*100 =0.25g Thus, percentage =0.25/0.5 =0.5 *100% =50% |
Re: Chemistry Guru's Help Out. by Odilop: 4:25pm On Nov 21, 2013 |
What are the two subtance which when react with oxygen and atp produces light in fire flies?? |
Re: Chemistry Guru's Help Out. by Nobody: 4:33pm On Nov 21, 2013 |
Odilop: Lmaooo!! Be nice. |
Re: Chemistry Guru's Help Out. by Nobody: 4:34pm On Nov 21, 2013 |
zhukafa: A sample of 0.500g of impure CaC03 was dissolved in 50.0cm³ of 0.100moldm–³ HCL and the remaining acid was titrated against 5.0cm³ of 0.12mol dm–³ NaOH solution. find the percentage of CaCO3 in the sample.IT'S LONG BUT GO THROUGH IT CAREFULLY CaCO3 + 2HCl ----> CaCl2 + H2O + CO2 ------- eqn 1 Mole ratio 1 : 2 no of moles of HCl= (50/1000)*0.100= 0.005mol NOTE THAT THIS IS IN EXCESS HCl + NaOH -------> NaCl + H2O ------------eqn 2 Mole ratio 1 : 1 no of moles of NaOH = (5.0/1000)*0.12= 0.0006 mol from eqn 2, no of moles of HCl= 0.0006 mol Actual no of moles of HCl that reacted in eqn 1 = Excess - Used = 0.005mol - 0.0006mol =0.0044mol Back to eqn 1 CaCO3 + 2HCl ----> CaCl2 + H2O + CO2 ------- eqn 1 Mole ratio 1 : 2 no of moles x : 0.0044 x = (0.0044*1)/2 = 0.0022 mol NOTE: 1 mol of CaCO3 = 100g 0.0022 mol of CaCO3 = 0.22g % of CaCO3 in sample = (Mass of CaCO3/Mass of mixture)*100 = (0.22/0.500)*100 = 44% 1 Like |
Re: Chemistry Guru's Help Out. by Odilop: 5:42pm On Nov 21, 2013 |
oluafolabi:how? |
Re: Chemistry Guru's Help Out. by zhukafa(m): 7:15pm On Nov 21, 2013 |
Dr_Bode: thanks I appreciate. but how sure is your answer and workings. |
Re: Chemistry Guru's Help Out. by zhukafa(m): 7:17pm On Nov 21, 2013 |
Odilop: thanks I appreciate. please review and tell me how sure you are. thanks in anticipation. |
Re: Chemistry Guru's Help Out. by Nobody: 7:46pm On Nov 21, 2013 |
zhukafa:I'm sure |
Re: Chemistry Guru's Help Out. by zhukafa(m): 7:54pm On Nov 21, 2013 |
Dr_Bode: thanks man |
Re: Chemistry Guru's Help Out. by FunmbiLayo(f): 9:28pm On Nov 21, 2013 |
Well..I just saw a mistake there @odilop. @Dr_bode...how did u get d no of moles of HCl there? |
Re: Chemistry Guru's Help Out. by Nobody: 9:45pm On Nov 21, 2013 |
FunmbiLayo: Well..I just saw a mistake there @odilop. @Dr_bode...how did u get d no of moles of HCl there? Which one exactly? Frm eqn 1 or eqn 2? |
Re: Chemistry Guru's Help Out. by Odilop: 1:32pm On Nov 22, 2013 |
Yap Dr bode was correct I did a mistake. Dr_Bode:the mole is correct. |
Re: Chemistry Guru's Help Out. by zhukafa(m): 1:35pm On Nov 22, 2013 |
Odilop: Yap Dr bode was correct I did a mistake.the mole is correct. thanks all, I appreciate. I also have some more questions for you friends to help me out with. I will post them later. once more, thanks. |
Re: Chemistry Guru's Help Out. by Odilop: 1:59pm On Nov 22, 2013 |
zhukafa:welcome bro.more question... |
Re: Chemistry Guru's Help Out. by zhukafa(m): 6:03pm On Nov 22, 2013 |
My Brothers and friends, thanks for your previous assistance. Still help with this one. thanks. 1) Mercury -197 is used for kidney scans and has a half-life of 3 days. If the amount of mercury-197 needed for a study is 1.0 gram and the time allowed for shipment is 15 days, how much mercury-197 will need to be ordered? 2) The half-life of strontium-90 is 25 years. How much strontium-90 will remain after 100 years if the initial amount is 4.0 g? 3) If the half-life of uranium-232 is 70 years, how many half-lives will it take for 10 g of it to be reduced to 1.25 g? |
Re: Chemistry Guru's Help Out. by zhukafa(m): 7:45pm On Nov 23, 2013 |
help out please. |
Re: Chemistry Guru's Help Out. by zhukafa(m): 7:42pm On Nov 24, 2013 |
still waiting |
Re: Chemistry Guru's Help Out. by zhukafa(m): 7:21am On Nov 25, 2013 |
Good morning friends |
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