30.0 mL of 0.50 M NaOH to neutralize 15.0 mL of HNO3, what is the concentration (molarity) of the HNO3?

1 answer:

4 0

First find the no. of moles of NaOH :
30/1000 = 0.3 dm3 so no. of moles = 0.3*0.5 = 0.15 moles 

as NaOH reacts with HNO3 in a ratio of one to one, there must have been 0.15 moles of HNO3 too 
moles/volume = concentration 
volume= 15/1000 = 0.15 dm3 

concentration = 1.15/0.15 = 1 mol.dm-3 

The quicker way would be to realize that you used twice as much NaOH so the HNO3 had to be twice as strong

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The mole fraction of iodine, i2, dissolved in dichloromethane, ch2cl2, is 0.115. what is the molal concentration, m, of iodine i

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<h3>Further explanation</h3>

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