Ask Me Help Desk - Chemistry

which one is the limiting reagent?

sarah1004 — Sat, 21 Nov 2009 01:04:00 GMT

A 10mL solution of 0.32M KOH was mixed with 25mL of 0.12M HBr solution. which one is the limiting reagent?

I think HBr is limiting reagent..........

Please help me

calculate the specific heat of the metal.

sarah1004 — Thu, 19 Nov 2009 18:54:36 GMT

A piece of a metal (34.9g) was heated to about 95C and then added to 550g water with the initial temperature of 28.2C. If the final temperature of the water and the metal is 31.2C, calculate the specific heat of the metal.

Do we have any formula for this problem?

Thanks

calculate the quantity of heat lost

sarah1004 — Thu, 19 Nov 2009 06:06:37 GMT

calculate the quantity of heat lost when 52g of S is cooled from 85C to 60C.
The specific heat of sulfur is 0.736J/g C.

Do i have to find mole of S first?

Please help the step to solve this problem.Thanks

given the reactants how do u find the products

stacey_113 — Thu, 19 Nov 2009 03:35:47 GMT

how do i find the products or these following reactants?

Na2CO3 +HCl

C6H12O6

CuSO4

AgNO3 + NaI

Chemical Reactions: Balanced Chemical Equations

claudia laura — Thu, 19 Nov 2009 02:04:45 GMT

How do you do a structural diagram of reactant molecules

2 no + )2 -> 2no3

structural digram of product molecules

what is the oxidation number of.

sarah1004 — Thu, 19 Nov 2009 00:39:26 GMT

what is the oxidation number of

Mn in MnCl2 --> +2
Mn in MnO4^- ---->
S in K2S4O6 ----------> +10
Cl in HCl ------>+1

I couldnt do (Mn in MnO4^- ---->) this one and also i am not sure on third one either..
Please help me ohh.. do i have to multiply coefficant to each molecule before looking for oxidation number?

write balanced chemical equation for the reaction, I did it! but i am not sure.

sarah1004 — Wed, 18 Nov 2009 06:27:31 GMT

write the balanced chemical equation for the reaction of Fe2+ with MnO4- in acidic solution.

I did it , but i am not sure. please check it for me

H^+ + MnO4^- + Fe2+ ---------------> Mn2+ + Fe3+ + H2O

I am reallly confusing this is True or not.

sarah1004 — Wed, 18 Nov 2009 05:42:45 GMT

a)△H for the reaction of NaOH and HCl solutions will be the same as △H for reaction of KOH and HNO3 solutions because the net ionic equation is the same in each case.

b)△H for the reaction of NaOH and HCl solutions will be different from △H for the reaction between LiOH and HBr because different salt is formed.

I think a is true and b is false...

If not.... I will think about it again please tell me >0<