Reactions with water: how you remember
Ask yourself:
“What can a metal in the reactivity series possibly produce with water?”
“What can K, Li or Mg + H2O produce?”
![Table showing metal and water react to produce hydroxide and hydrogen](/images/user/base/Chemistry/8. The Metal Reactivity Series/Reactions with water how you remember/reactions-with-water---metal-and-water-1.d28a5c1.jpg)
![Table showing metal and water react to produce oxide and hydrogen](/images/user/base/Chemistry/8. The Metal Reactivity Series/Reactions with water how you remember/reactions-with-water---metal-and-water-2.c2371b0.7e484e2.jpg)
Wow, it’s that easy!
Let's say that cold water does not separate all the hydrogen from oxygen.
Let’s also say that steam separates all the hydrogen from the oxygen, so:
Cold water | + | reacting metal | → | (metal) hydroxide | + | Hydrogen |
(metal) OH | + | H2 |
But
Steam | + | reacting metal | → | (metal) oxide | + | Hydrogen |
(metal) O | + | H2 |
Example 1
Water | + | Magnesium | → | Magnesium hydroxide | + | Hydrogen |
2H2O | + | Mg | → | Mg(OH)2 | + | H2 |
Example 2
Steam | + | Magnesium | → | Magnesium oxide | + | Hydrogen |
H2O | + | Mg | → | MgO | + | H2 |
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![](/images/user/base/Maths/Logarithms/Reference%20Tables/reference-anti-log-table-1.b0b0513.jpg)
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