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Recent content by Abdel Moniem

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    Chemistry: Post your doubts here!

    2 is acceptable because the overlap of the orbital of the H and I atoms produces a longer bond length thus bond strength is lower. Less energy is then required to break the H--I bond. 3 is incorrect because any decomposition requires the input of energy(endo).
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    Chemistry: Post your doubts here!

    PCl5(g)-->PCl3(g)+Cl2(g) Enthalpy Change=Enthalpy change of bonds broken+ Enthalpy change of bonds formed 2 P-Cl bonds were broken and a Cl-Cl bond was formed
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    Expected Chemistry P11 GT

    C had an NH2 or an NH3+
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    Expected Chemistry P11 GT

    Compound X was 1,5 dibromooctane
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    Expected Chemistry P11 GT

    Do you remember what the name of the cyclic structure was containing NH, ester and a ketone?
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    Chemistry: Post your doubts here!

    The question with both an NH group and an ester group what was the answer for that?
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    Chemistry: Post your doubts here!

    Oxygen in the air reacts with sulphur dioxide to form sulphur trioxide which then reacts with calcium oxide to form calcium sulphate.
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    Chemistry Paper 51

    yes you are right about the endothermic thing just thought about it now i am sorry guys. why is it 245cm^3. You got me worried is there many incorrect answers?. if there is an incorrect answer i am sure its the 2nd part of q2).
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    Chemistry Paper 51

    When the Delta H of solution is positive the solubility is low, but it clearly stated in the question that solubility increases with temperature so it must be exothermic. I am not sure too.
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    Chemistry: Post your doubts here!

    CCl2=CH-CH3 CHCl=CClCH3 (This can form a cis and trans isomer) CH2=CClCH2 CH2=CHCHCl2
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    Chemistry: Post your doubts here!

    Cl2+2NaOH-->NaCl+NaClO+H2O Number of moles=Mass(g)/Molar Mass(g/mol), rearrange to get the mass as the subject of the formula. According to the chemical equation, all of the products are 1:1 to Cl2 in terms of mole ratio. Calculate the Mass of each product by calculating the Mr of each of the...
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    Chemistry Paper 51

    my answers for the paper HCO2-->CO2+H+ +2e- MnO4+5e-+8H+-->4H2O+Mn2+ I think concentration was 1. something where i used Mr*Concentration(mol/dm^3)=Concentration(g/dm^3) and for the methanoate ions it was 2*1. something i don't quite remember the calculation part. to prepare a concentration...
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    Maths P3 2015 All Questions And Answers.

    Now i understood the question of complex number in ii) but i havent read the question right i used the same step as its done in the answers but ofcourse with different number so i used the square root of u. For q10ii) the plane question i have found a common perpendicular between point A and the...
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    Mechanics Paper 5 2015. Post your Problems here!!

    http://freeexampapers.automaticpapers.com/as-a-level/mathematics-9709/9709_s13_qp_51.pdf Q7
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    Chemistry p41: How'd it go peeps?

    thanks god!, in the x-ray diffraction i said that phosphorus would produce the most intense spot because it contains the most electrons. i draw out a key lock model in the enzyme question explained how a substrate binded into the enzyme's active site. enzymes catalysis the reaction and the...
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