# Question #533df

##### 1 Answer

#### Explanation:

The hydrated magnesium sulfate contains water of crystallisation which is driven off when heated:

By recording the loss in mass we can find the mass of water and then convert masses into moles to find

Mass

Mass

So mass water lost =

Now we need to convert grams into moles using:

Number of moles = mass in grams/mass of 1 mole

Or:

We get this by adding all the relative atomic masses (

Using accurate

You should use the

Now using

and:

So we now know that the ratio in moles of:

We like to express this ratio in whole numbers according to how the atoms/molecules combine so we can divide both numbers by

Which is good enough (in my book) as:

So

Here is a full lab on hydrate and how to calculate the formula of a hydrate, I hope this helps more: