[integral0]

2. What is the total concentration of NO3- when 2.50 mL of 0.30 M Fe(NO3)3 in 0.10M HNO3 in 0.10M HNO3 is diluted to 10.0 mL with water?
a. 0.75 M NO3-  b. 0.10M NO3-  c. 0.19 M NO3- d. 0.08 M NO3-  e. 0.21 M NO3-


I took CFe = .30M x (2.50ml/10ml) x 3 = .225 M NO3...which is close to the answer of 0.21 M NO3-

ANy idea?

The answer is e.

[Borek]

IMHO right answer is f. 0.25M

You forgot about 0.1M HNO3.