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Do u have facebooook????????????????I don't hv one lol ...can't u draw n post it here?
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Do u have facebooook????????????????I don't hv one lol ...can't u draw n post it here?
Could anyone help me with this. Looks easy but my results don't match!!!!!
12 Use of the Data Booklet is relevant to this question.
This question should be answered using bond enthalpy data. The equation for the complete combustion of methane is given below.
CH4 + 2O2 → CO2 + 2H2O
What is the enthalpy change of combustion of methane?
A –1530kJ mol–1
B –1184kJ mol–1
C –770kJ mol–1
D –688kJ mol–1
Your answer is correct, but if you look in the Data Booklet, In the Bond Energies section in polyatomic molecules section: there are different values for C double bond C and C Double Bond C in CO2.To my inadequate knowledge the answer is "D"
CH4 + 2O2 → CO2 + 2H2O
Bond energy of reactants:
=4(410)+2(496)
= +2632 kj/mol
now look at The bond energy of Products:
= 2 (740)+ 4 (460)
= +3320 kj/mol
last step:
enthalpy change = B.E of Reactants - B.E. of Products
= 2632 -3320
= - 688 kj/mol
HOPE IT HELPS!
Try Z notes or chemguide there's plenty of notes on the internet <33Does anyone have complete ORGANIC notes I lost mine I (need them for the MCQ exam because I forgot most of the reactions and important points)
I will be really grateful if someone shares their...
Does anyone have complete ORGANIC notes I lost mine I (need them for the MCQ exam because I forgot most of the reactions and important points)
I will be really grateful if someone shares their...
OHHHH This got me into a trap too!A sample of ethyl propanoate is hydrolysed by heating under reflux with aqueous sodium hydroxide. The two organic products of the hydrolysis are separated, purified and weighed. Out of the total mass of products obtained, what is the percentage by mass of each product?
A 32.4% and 67.6%
B 38.3% and 61.7%
C 42.3% and 57.7%
D 50.0% and 50.0%
answer is A
PLEASE HELP
ANY HELP WILL BE APPRECIATED
N2(g) + 3H2(g) 2NH3(g)
volume of M = V
OHHHH This got me into a trap too!
SO basically You have to know that HYDROLYSIS OF ESTERS WITH NAOH ------> SODIUM SALT OF CARBOXYLLIC ACID + THE ALCOHOL
so make the equation : CH3CH2COOCH2CH3 + NAOH -------> CH3CH2COONA + CH3CH2OH
THEN assume you have one mole of ethyl ethanoate, so you will have 1 mole of all the products, the salt and the alcohol
multiply the moles with the MR of the products to find mass, you will get 96g of the salt and 46g of the alcohol
DON'T FORGET TO FIND TOTAL MASS WHICH IS 142G
THEN just find percentage by mass of total mass : { 46/142} X 100 = 32.4% and for the other one 67.6%
HOPE THIS HELPS YOU
You are welcome anytime!!!THANK YOU SO MUCH FOR THIS HELP
A is the answer as H + and Cl + and O 2- (overall 0 so this is correct )Which compound contains two different elements with identical oxidation states?
A HCl O B Mg(OH)2 C Na2SO4 D NH4Cl
someone please help
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