Please help with question so urgent!!!

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Fifty345
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You will need the following data to answer these questions.
Relative atomic mass of hydrogen = 1
relative atomic mass of magnesium = 24

24g of magnesium was reacted with excess hydrochloric acid.
Calculate how many moles of magnesium reacted. I got 1 mole.

This is the question i need help with.
Calculate how many moles of hydrogen gas would be formed.
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charco
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(Original post by Fifty345)
You will need the following data to answer these questions.
Relative atomic mass of hydrogen = 1
relative atomic mass of magnesium = 24

24g of magnesium was reacted with excess hydrochloric acid.
Calculate how many moles of magnesium reacted. I got 1 mole.

This is the question i need help with.
Calculate how many moles of hydrogen gas would be formed.
Your first step is to write out an equation for the reaction ...
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Fifty345
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(Original post by charco)
Your first step is to write out an equation for the reaction ...
magnesium plus hydrochloric acid is magnesium plus hydrogen gas
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s666
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Mg + 2HCl ---> MgCl2 + H2

One mole of magnesium reacts with two moles of HCL to form one mole of magnesium chloride plus one mole of hydrogen gas.... One mole magnesium makes one mole of hydrogen gas
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charco
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(Original post by Fifty345)
magnesium plus hydrochloric acid is magnesium plus hydrogen gas
This is NOT an equation ...
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Fifty345
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(Original post by s666)
Mg + 2HCl ---> MgCl2 + H2

One mole of magnesium reacts with two moles of HCL to form one mole of magnesium chloride plus one mole of hydrogen gas.... One mole magnesium makes one mole of hydrogen gas
so would that mean that the answer is 24 moles of hydrogen gas would be formed
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s666
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You just said that one mole of magnesium reacted though?? So one mole of Hydrogen gas is formed no?
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charco
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(Original post by Fifty345)
so would that mean that the answer is 24 moles of hydrogen gas would be formed
There are 3 moles equations to learn:

1. For pure substances

moles = mass/relative mass

2. For solutions

moles = molarity x volume

3. For gases

moles = volume(litres)/24 (at room temperature and pressure)

--------------------------------------------------------------------------------

Which do you suppose applies here?
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Fifty345
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(Original post by charco)
There are 3 moles equations to learn:

1. For pure substances

moles = mass/relative mass

2. For solutions

moles = molarity x volume

3. For gases

moles = volume(litres)/24 (at room temperature and pressure)

--------------------------------------------------------------------------------

Which do you suppose applies here?
the first one
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Fifty345
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(Original post by s666)
You just said that one mole of magnesium reacted though?? So one mole of Hydrogen gas is formed no?
so your saying that for every one mole of magnesium is created, one mole of hydrigen gas is created. idk....
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Fifty345
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(Original post by Fifty345)
the first one
moles = mass/mr
= 1 (mass) / 1 (mr)
=1 mole

thanks
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s666
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Yeah so if you look at the equation, you can see that one mole of Mg reacts with 2mol HCl to form 1mol of MgCl2 and 1mol hydrogen gas. The numbers (or lack of) infront of the reactants and products show the moles that react.

So yes one mole of magnesium reacts to form 1 mole of hydrogen gas
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