Question

Medal and fan
If 25 mL of a .5 M NaOH solution were needed to reach the equivalence point of a 20 mL HCl solution, what is the original analyte concentration?

Since I'm new to this side of chem, I don't know how to answer this question whatsoever.

Answer 1

NaOH+HCl-->NaCl+H2O
Number of moles=Concentration*volume
N=0.5*25/1000=0.0125 moles
Ratio of Moles of NaOH to HCl is 1:1
0.0125=Concentration*20/1000
20C/1000=0.0125
0.0125*1000/20=0.625 mol/dm^3

Answer 2

Where do you get the 1000 from?

Answer 3

Iam changing the volume unit from ml to dm^3

Answer 4

Ohhh alright. Thankyou!

Answer 5

your welcome :)