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# Quantity Question watch

1. Hi, trying to wrap my head around this quantity question.
How much sodium hydroxide is required to manufacture 7.8 g of sodium sulfate?
It's from the equation
sodium hydroxide + sulfuric acid -> sodium sulfate + water
And if you could explain how to do this it'd be great, thanks in advance.
2. (Original post by usingnamespace)
Hi, trying to wrap my head around this quantity question.
How much sodium hydroxide is required to manufacture 7.8 g of sodium sulfate?
It's from the equation
sodium hydroxide + sulfuric acid -> sodium sulfate + water
And if you could explain how to do this it'd be great, thanks in advance.
Write the chemical equation so that you can figure the molar ratio between NaOH and Na2SO4

Calculate the moles in 7.80g of Na2SO4 and, using the ratio, calculate the moles of NaOH.

Then calculate the mass.

Tada. All that calculating part is for you.
3. (Original post by usingnamespace)
Hi, trying to wrap my head around this quantity question.
How much sodium hydroxide is required to manufacture 7.8 g of sodium sulfate?
It's from the equation
sodium hydroxide + sulfuric acid -> sodium sulfate + water
And if you could explain how to do this it'd be great, thanks in advance.
Spoiler:
Show

First write out the reaction equation

Work out the molar mass for sodium sulphate: 142 g/mol
n=m/gfm = 7.8/142 = 0.055 mol
Multiply by two since the ratio is 2:1
=0.11 mol NaOH required
Work out the molar mass of NaOH: 40 g/mol
m=n*gfm = 40 * 0.11 = 4.4 g
4. (Original post by RMNDK)
Write the chemical equation so that you can figure the molar ratio between NaOH and Na2SO4

Calculate the moles in 7.80g of Na2SO4 and, using the ratio, calculate the moles of NaOH.

Then calculate the mass.

Tada. All that calculating part is for you.
I did manage to work this out on my own, to which I got 4.4g, but thankyou for the help! Had an extremely bad teacher for C2!
5. (Original post by langlitz)
Spoiler:
Show

First write out the reaction equation

Work out the molar mass for sodium sulphate: 142 g/mol
n=m/gfm = 7.8/142 = 0.055 mol
Multiply by two since the ratio is 2:1
=0.11 mol NaOH required
Work out the molar mass of NaOH: 40 g/mol
m=n*gfm = 40 * 0.11 = 4.4 g
Thanks for the help! I managed to wrap my head around it.

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