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This is not MV=MV? NV=NV?
Is N= g/L? Thanks.
Is N= g/L? Thanks.
Gen chem question
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Hi,
n = number of moles
c = concentration (i.e. 2M 4M...)
m= number of grams = weight
M = molecular weight
n=cV = m/M
you only need n=cV here. To neutralize n(H) = n(OH) tag H to 1 and OH to 2
so it's c1V1=c2V2 or 2M*V1 = 2M*200ml so V1 seems to be 2M.
But there are 2H+ in each H2SO4 but only 1OH- in NaOH so you need only half = 1M.
n = number of moles
c = concentration (i.e. 2M 4M...)
m= number of grams = weight
M = molecular weight
n=cV = m/M
you only need n=cV here. To neutralize n(H) = n(OH) tag H to 1 and OH to 2
so it's c1V1=c2V2 or 2M*V1 = 2M*200ml so V1 seems to be 2M.
But there are 2H+ in each H2SO4 but only 1OH- in NaOH so you need only half = 1M.
U can look at it like this and not do any calculation:
the Normal for H2SO4 is 2 (supplies 2 H+)
the Normal for NaOH is 1 (supplies 1 OH)
So if you have 200mL of NaOH, how much H+ do u need to get it back down to a pH=7? Well since H2SO4 will give you 2 H+ when it dissociates, you will only need HALF as much H2SO4 as NaOH inorder for the amount of H+ to equal the amount of OH- and thus, balance the pH.
Ans. 100mL
If you were using HCl, you need an equal amount of it, 200mL, because HCl only provides 1 H+ so equal amounts of HCl and NaOH are required to balance the pH
the Normal for H2SO4 is 2 (supplies 2 H+)
the Normal for NaOH is 1 (supplies 1 OH)
So if you have 200mL of NaOH, how much H+ do u need to get it back down to a pH=7? Well since H2SO4 will give you 2 H+ when it dissociates, you will only need HALF as much H2SO4 as NaOH inorder for the amount of H+ to equal the amount of OH- and thus, balance the pH.
Ans. 100mL
If you were using HCl, you need an equal amount of it, 200mL, because HCl only provides 1 H+ so equal amounts of HCl and NaOH are required to balance the pH
