[nisha1]

if i have 10mL of concentrated solution (concentration unknown) of a perticular compound. Now if i dilute it 10 times by adding 100mL of distilled water. how can i find the concentration of that concentrated solution.

[AWK]

You dilute your solution 11 times (not 10) in this case. Without known concentration you cannot calculate  the concentration of diluted solution.

[nisha1]

if i have 10mL of concentrated solution (concentration unknown) of a perticular compound. Now if i dilute it 10 times by adding 100mL of distilled water. how can i find the concentration of that concentrated solution.

sir if we find out the concentration of diluted sample by analyzing solutions of different concentration using UV/Vis spectrophotometer how can we calculate the concentration of the concentrated 10mL sample of that substance. the problem is that UV/Vis can detect dilute solutions upto absorbance=2 and i am having the concentrated sample whose concentration is unknown. i just want to verify my answer with your answer.
say, if we take 10mL of concentrated solution in 100mL volumetric flask and then makeup to the mark with distilled water and if dilute solution analyzed is of 5N then the conc. of unknown is coming out to be 50N. Is it correct?

[Borek]

http://www.chembuddy.com/?left=concentration&right=dilution-mixing