## anonymous 4 years ago 50 ML of 0.001 M phosphoric acid are exactly neutralized by the addition of 0.005 N Naoh the molarity of resulting salt is?

1. anonymous

@Callisto help

2. Callisto

Sorry.. I haven't learnt it :|

3. anonymous

ok

4. .Sam.

$\begin{array}{c} \text{H}_3\text{P}\text{O}_4 \\\end{array}\text{ + }\begin{array}{cc} 3 & \text{Na}\text{O}\text{H} \\\end{array}\text{ \longrightarrow  }\begin{array}{cc} 3 & \text{H}_2\text{O} \\\end{array}\text{ + }\begin{array}{c} \text{Na}_3\text{P}\text{O}_4 \\\end{array}$ ------------------------------------ $M_AV_A=M_BV_B$ $\text{Molarity of base is}~~ M_B$ $\text{Molarity of acid is}~~ M_A$ ------------------------------------ $M_B=\frac{M_AV_A}{V_B}$ Sub in the values

5. Preetha

Don forget the stoichiometric ratios. for every mole of phosphoric acid, you need 3 moles of NaOH to neutralize it. So you have to include that factor of 3 in the above calculation. It is a 1: 3 not 1:1 relationship. Try it and see.

6. anonymous

@Kryten help!

7. anonymous

as i see it you got all you need you just need to put numbers in.... only way to learn how to solve this kind of things is to do it yourself...

8. anonymous

i solve it but not getting lol @Kryten thats why i called u

9. anonymous

if u get after solving that then inform me

10. anonymous

The answer should be 6.25 * 10^-4 moles

11. anonymous

but i am not getting that @Kryten

12. anonymous

this is really basic chemistry, begin with writing equation, then write down what you have and what you need and do the magic... put the relationships of reactants and products in equations and just crunch the numbers...

13. anonymous

@.Sam. not getting the answer by ur way

14. anonymous

@Kryten not getting!!!

15. anonymous

i wrote the equation

16. .Sam.

6.25 * 10^-4 moles This is in moles, I thought you want molarity?

17. anonymous

@Kryten do u have any idea

18. anonymous

i am confused in question it is asked to find molarity but the answer is given in 6.25*10^-4

19. anonymous

yea i have some idea but i gotta run students arent waiting i need to keep them safe... see you later

20. anonymous

@Vincent-Lyon.Fr do u have any idea....

21. anonymous

I won't answer any of your questions as you are pestering this study site without ever doing any effort on your own.

22. anonymous

@Vincent-Lyon.Fr i did but not getting!

23. anonymous

@open_study1 , my answer is same as @Vincent-Lyon.Fr 's

24. anonymous

@shivam_bhalla i tried ny level best but i am unable,

25. anonymous

@.Sam. and @Preetha have given you the valuable hints and tips . Just go ahead and solve it. you have to find the number of moles of H3PO4 initially reacting from given info

26. anonymous

What's M and N?

27. anonymous

M=molarity N=normality

28. anonymous

moles = 5*10^-5 moles

29. anonymous

Yes. Now continue and do the rest of the problem.

30. anonymous

now wat to do

31. anonymous

I'm sorry i don't know this :).

32. anonymous

@shivam_bhalla r u there....

33. anonymous

Plzzz help anyone plzz!

34. anonymous

@Kryten HELP

35. anonymous

I FOUNDED THE MOLE THEN WAT TO DO???

36. anonymous

@Kryten PLZZ GUIDE ME PLZZ

37. anonymous

OH........OH..........PLZZZZ SOME ONE HELP! I AM WAITING FOR 1 DAY PLZZZZ

38. anonymous

5*10^-5 moles

39. anonymous

in your place i would give up on pleading and solve it myself... you have been give instructions by multiple people and you just need to follow them, point is that you want it to be solved so you god forgive wouldnt have to hitch your little grey cells...

40. anonymous

I DID IN THE WAY THEY GUIDED BUT NOT GETTING I FOUNDED THE MOLES THEN WAT TO DO PLZZ TELL ME THE STEPS I WILL SOLVE MY OWN @Kryten

41. anonymous

first send some proof that you did anything (picture of paper of your tries) and then ill help. this is i think your third time you post this question and you just need to read what people have written... look up and read all carefully

42. anonymous

0.15=0.005*V V=30ML

43. anonymous

0.05 MILLI MOLES OF H3PO4 ON REACTING GIVES 0.05 MILLI MOLES OF NA3PO4 IE 5*10^-5 MOLES OF NA3PO4 ARE FORMED

44. anonymous

@Kryten

45. anonymous

46. anonymous

now lets start from the begining write first what data you have, chemical reaction equation and then write what you need from data to be calculated

47. anonymous

H3PO4 + 3NaOH ⟶ 3H2O + Na3PO4

48. anonymous

WE HAVE TO FIND THE MOLARITY OF NA3PO4

49. anonymous

write your data properly ex. c(X)= ... V(X)=... c(Y)=.... and then what you need to calculate ex. c(z)=?

50. anonymous

WAT IS C(X)

51. anonymous

that are examples how to write your data properly now lets see you do it

52. anonymous

V(PHOSPHORIC ACID)=50ML M(PHOSPHORIC ACID)=0.001M N(NAOH)=0.005N M(NA3PO4)=?

53. anonymous

IS THAT CORRECT.........

54. anonymous

ok now lets see you have written N(NaOH)=0,005N --> that doesnt exist cause N(NaOH) is marking of number of NaOH atoms and it has no units, and furthermore write it one under another not one next to other cause that is vast. now lets see corection...

55. anonymous

NORMALITY OF NAOH=0.005N

56. anonymous

now please explain to me what is normality and then write all data again properly

57. anonymous

NO OF EQUIVALENT OF SOLUTE IN ONE LITRE OF SOLUTION

58. anonymous

ok now explain me the unit N what is its derivative

59. anonymous

N= WG OF SOLUTE /(EQUIVALENT WG OF SOLUTE * VOLUME(L))

60. anonymous

ok now when you explained it all carry on and write all data properly one item under other and under it all chemical equation

61. anonymous

@Kryten ANYHOW THANZZZ I HAVE TO GO NOW PLZZ GIVE ALL THE HINTS I WILL LOOK IT AFTER WARDS............

62. anonymous

no way, you will write all here so i see what you are doing...

63. anonymous

hello

64. anonymous

@Kryten

65. anonymous

continue where you stoped, write all on one place...

66. anonymous

thats all wat i knw

67. anonymous

but you still havent written all in one place properly

68. anonymous

oh....no wat else u want

69. anonymous

i would like a cold bear and a steak but what you want is the question

70. anonymous

this website was made to help!!!! so plzz

71. anonymous

i am helping you but you are resisting to it... take a look how i solved your past questions where i photographed my work, it was all in sequence like it should be and that is the only way i will help you if you do it properly and as it should be solved and when you get that routine all this will be easy for you so your choice...

72. anonymous

yes u helped me a lot earlier by risiking a lot but i want the reson now why u r not helping that way did any one force u???

73. anonymous

such as @vincent fr @aravind etc......

74. anonymous

no, but i realised that you are taking a path of least resistance which is not good... this site is for learning and not getting all solved with no effort...

75. anonymous

now lets skip all the debate and tell me if you want to do it with my help properly or with no help at all

76. anonymous

i want help

77. anonymous

so whats the problem then... take a look how i solved your past questions and write it all like that here step by step and with understanding and reason why is it like it is for each step so that you LEARN how to solve problems like this...

78. anonymous

ok let me try

79. ujjwal

Its been two days.. LMAO..

80. anonymous

yes no one seems to help me........

81. anonymous

Is the Answer 3.33 x 10^-4 ?

Find more explanations on OpenStudy