Science

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Science

• Balancing Equations

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WATER is made from OXYGEN and HYDROGEN
Hydrogen Oxygen Water
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Thats two hydrogen atoms and one oxygen atom to
make one molecule of water.
H
H
O
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The problem is ..

• Hydrogen goes around in twos, as H2
• Oxygen also goes around in twos, as O2

H
H
O
O
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So when Water is made

• Theres an oxygen atom left over

H
H
O
. And that doesnt happen!
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So we do some balancing

• We makes sure we use enough hydrogen
• so we dont have any leftover single oxygen
  atoms. Lets try two of hydrogen2.

But still only one oxygen2 molecule ..
? 2H2O
2H2
O2
2H2O means 2 molecules of H2O (water) are made
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So two H2 molecules bond with only one O2
molecule
? 2H2O
2H2
O2
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Which looks like this.
2H2 O2 ? 2H2O
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Thats why we add extra molecules of reactants.
But we must always make sure that these extra
amounts are also added to the product of the
equation.