# Question #3c82d

##### 1 Answer

Mass of calcium nitrate: **1200 kg**

#### Explanation:

The idea behind this problem is that you first need to determine how much nitrogen is supplied *per mole* of calcium nitrate, then use this value to determine how much you'd get *per gram* of calcium nitrate.

In other words, you need to determine the percent composition of nitrogen in

This important thing to notice is that you get **2 moles** of nitrogen per mole of calcium nitrate, which means that you have

This means that, for *every 100g* of calcium nitrate, you get **17.1 g** of nitrogen.

Since you're dealing with a **10-hectare** field, you need to supply a total of

You can express this value in grams to get

Since you need **100g** of calcium nitrate to get **17.1 g** of nitrogen, you can determine that

You can convert this back to kilograms if you want

Now, I'll leave the answer rounded to two sig figs, despite the fact that you only gave one sig fig for the mass of nitrogen and area of the field.