tag:blogger.com,1999:blog-5690887427829940237.post3907775961981172757..comments2024-01-16T00:26:39.356-08:00Comments on IGCSE Chemistry: 1.26 calculate percentage yieldHannahHelphttp://www.blogger.com/profile/03691395988069139300noreply@blogger.comBlogger12125tag:blogger.com,1999:blog-5690887427829940237.post-33233648196259525982018-10-24T14:09:25.460-07:002018-10-24T14:09:25.460-07:00and then find actual yeild by the formula and the ...and then find actual yeild by the formula and the actual yield will be givenAnonymoushttps://www.blogger.com/profile/05452589176434042345noreply@blogger.comtag:blogger.com,1999:blog-5690887427829940237.post-90627307184230595732018-10-24T14:08:37.527-07:002018-10-24T14:08:37.527-07:00Calculating Theoretical yield
Theoretical yield ...Calculating Theoretical yield <br /><br />Theoretical yield is actually the mass of product you will get (in calculations not real life). It can only be specific compound not more then one.<br /><br />To find theoretical yield you first have to know the amount of substances used.<br /><br />For example <br /><br />2h2o + ar3 = 4hg5<br /><br />this means that 2 moles of h2o produces 4 moles of hg5 <br />and also<br />1 mole of ar3 produces 4 moles of hg5<br /><br />now one of the reactant's mass\weight will be given<br /><br />for example h20 is 20 grams<br /><br />so 2 moles of h20 is 2x20 grams = 40 grams<br /><br />so now lets find the mass\weight of product(hg5)(Theoretical yield )<br /><br />so first<br /><br />convert the grams into moles of h20<br /><br />now we need RFM (Relative Formula Mass) of the substance<br /><br />for example h20 has RFM of 10 (it will also be given)<br /><br />mass of one mole is RFM<br /><br />number of moles = mass of substance/mass of one mole of the substance<br /><br />so 40 /10 = 4<br /><br />so 4 moles of h20 is used in this reaction <br /><br />so if 4 moles of h20 is used then we will get 8 moles of hg5<br /><br />because<br /><br />2h2o + ar3 = 4hg5<br /><br />this means that 2 moles of h2o produces 4 moles of hg5 <br />so <br /><br />4h2o + 2ar3 = 8hg5<br /><br />this means 4 moles of h20 is used then we will get 8 moles of hg5<br /><br />(same math increased moles as we have more moles of h2o)<br /><br /><br />so moles of hg5 is 8 in this reaction<br />so now we will find the mass/weight of hg5 by its moles <br /><br />so need to figure out the RFM because<br /><br />it will also be given so lets take it as 23<br /><br />number of moles = mass of substance/mass of one mole of the substance<br /><br />mass of one mole is RFM<br /><br />so let "mass of substance" be $$<br /><br />8 = $$ / 23<br /><br />so $$ = 23 x 8<br /><br />so thats the theortical of hg5<br /><br />Anonymoushttps://www.blogger.com/profile/05452589176434042345noreply@blogger.comtag:blogger.com,1999:blog-5690887427829940237.post-83522417290881341712017-04-04T01:17:52.169-07:002017-04-04T01:17:52.169-07:00If you got 70g from expected Fe, and 62 for actual...If you got 70g from expected Fe, and 62 for actual Fe, wouldn't it be 62/70 = 0.8857 = 88.57% ?Anonymoushttps://www.blogger.com/profile/00092926111088189796noreply@blogger.comtag:blogger.com,1999:blog-5690887427829940237.post-8241548662126158362016-11-30T07:39:43.816-08:002016-11-30T07:39:43.816-08:00THe question is wrong
THe question is wrong<br />Malikhttps://www.blogger.com/profile/02045113533020499275noreply@blogger.comtag:blogger.com,1999:blog-5690887427829940237.post-49124303471237752442016-04-08T07:00:52.447-07:002016-04-08T07:00:52.447-07:00someone help, why is it 62 over 80? and not 100?someone help, why is it 62 over 80? and not 100?Anonymoushttps://www.blogger.com/profile/01305093674388070670noreply@blogger.comtag:blogger.com,1999:blog-5690887427829940237.post-57894731269582825492016-01-12T13:40:44.444-08:002016-01-12T13:40:44.444-08:00You screwed this question up at the end the actual...You screwed this question up at the end the actual yield I.e 82g should be lower than the theoretical yield as nothing is able to have conversion rates of 100% and therefore the next part is wrong it should be 82/70 which makes no sense as the yield is greater than 100% as you got the actual yield wrong Anonymoushttps://www.blogger.com/profile/16901443029115660224noreply@blogger.comtag:blogger.com,1999:blog-5690887427829940237.post-85311701987603514902015-12-22T09:25:30.475-08:002015-12-22T09:25:30.475-08:00where does the 82g come from ?where does the 82g come from ?Anonymoushttps://www.blogger.com/profile/04111469028225622670noreply@blogger.comtag:blogger.com,1999:blog-5690887427829940237.post-38101416533829592872015-06-30T04:28:33.717-07:002015-06-30T04:28:33.717-07:00160 is the atomic mass of the molecule, this is wo...160 is the atomic mass of the molecule, this is worked out by adding together the individual atomic masses of all the particles, so in this case:<br />Fe= 56<br />O=16<br />(2*56) + (3*16)= 160HannahHelphttps://www.blogger.com/profile/03691395988069139300noreply@blogger.comtag:blogger.com,1999:blog-5690887427829940237.post-44779527333611082502015-06-28T05:44:33.642-07:002015-06-28T05:44:33.642-07:00Where did you get the 160 from? Where did you get the 160 from? Anonymoushttps://www.blogger.com/profile/09283824085557841519noreply@blogger.comtag:blogger.com,1999:blog-5690887427829940237.post-72382827878771293312015-06-17T16:07:29.624-07:002015-06-17T16:07:29.624-07:00Ar is relative atomic mass
Mr relative molecular m...Ar is relative atomic mass<br />Mr relative molecular massHannahHelphttps://www.blogger.com/profile/03691395988069139300noreply@blogger.comtag:blogger.com,1999:blog-5690887427829940237.post-72783130822685166722015-05-12T23:02:55.026-07:002015-05-12T23:02:55.026-07:00Wut is Ar and Mr?Wut is Ar and Mr?Anonymoushttps://www.blogger.com/profile/05445231351278119508noreply@blogger.comtag:blogger.com,1999:blog-5690887427829940237.post-9202594637701690502014-08-24T06:44:04.120-07:002014-08-24T06:44:04.120-07:00"Now we have moles of Fe we can work out weig..."Now we have moles of Fe we can work out weight by Mol x Ar: 1.25 x 56= 70g"<br />Shouldn't it be Mol x Mr, as it is is 2Fe? So, it would be 1.25 x 112 = 140g?Anonymoushttps://www.blogger.com/profile/14779589184394253720noreply@blogger.com