Concentration and pH?

Question

equal volumes of 0,1 M HCl and 0,1M NaOH solutions were miced. concentration of NaCl and pH of the final solution respectively were:

correct>: 0,05 pH = 7

i tried this way. I say the volume is 1dm3. Then i multiply the concentration with 1dm3. Then i have the molar mass. 0,1mol

0,1x 2 (its two) ............= 0,1M
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new volume(1+1=2)

Answer 1

the equation is :

HCl + NaOH >> NaCl + H2O

we have the same number of moles so the solution is neutralized and pH =7

0.1 M means 0.1 mole per Liter

total volume = 2 L

0.1 / 2 = 0.05 M

Answer 2

The HCl is a strong acid and the NAOH is a strong base. As both got the same concentration and volume, you can assume that both neutralize completely (meaning that they will produce a salt and water) so pH = 7. There will be no concentration of HCl or NaOH but for NACl you can follow the chemical equation:
HCl + NaOH => NaCl + H2O
as you are using .1 mol of each of every 1 L, and the final volume is the double of the first, the concentration of the salt NaCl will be 0.05M.

Answer 3

This is correct.

Say the volume of each 0,1 Molar solution is 1 Litre.

Thus, you're mixing 0,1 mol of HCl + 0,1 mol NaOH + 2 Litres of water.

Equal amounts of these reagents will result in a neutral pH (7).

HCl + NaOH ---> NaCl + H2O

0,1 mol HCl + 0,1 mol NaOH will product 0,1 mol NaCl.

Thus, [NaCl] = 0,1 mol / 2 Litres
[NaCl] = 0,05 M

Answer 4

Use the Normality eqn.