Photo AI
The gas dinitrogen oxide (N₂O) can be used as an anaesthetic - Leaving Cert Chemistry - Question c - 2018
Question c
The gas dinitrogen oxide (N₂O) can be used as an anaesthetic. It can be made by decomposing ammonium nitrate (NH₄NO₃) using heat according to the following balanced ... show full transcript
Worked Solution & Example Answer:The gas dinitrogen oxide (N₂O) can be used as an anaesthetic - Leaving Cert Chemistry - Question c - 2018
Step 1
Step 2
What is the mass in grams of one mole of ammonium nitrate (NH₄NO₃)?
Answer
To calculate the mass of one mole of NH₄NO₃, we add the atomic masses of all its constituent elements:
- N: 14 g/mol (2 N)
- H: 1 g/mol (4 H)
- O: 16 g/mol (3 O)
Thus,
ext{Mass of } NH₄NO₃ = (14 + (1 imes 4) + (16 imes 3)) ext{ g} = 80 ext{ g/mol}.
Step 3
When 16 g of NH₄NO₃ react according to the equation above, how many moles of water are formed?
Answer
First, we determine the number of moles of NH₄NO₃:
egin{align*}
n &= rac{mass}{molar ext{ mass}}
&= rac{16 g}{80 g/mol} = 0.2 ext{ moles NH₄NO₃} \
ext{From the balanced equation, } 2 moles ext{ of } H₂O ext{ are produced per mole of } NH₄NO₃.\
ext{Thus, } 0.2 ext{ moles of } NH₄NO₃ ext{ will yield } 0.2 imes 2 = 0.4 ext{ moles of } H₂O.
ext{Therefore, } 0.4 ext{ moles of water are formed.}
ext{ }
Step 4
What volume does the N₂O gas produced occupy at s.t.p.?
Answer
Since 0.2 moles of NH₄NO₃ produces 0.2 moles of N₂O, we can use the molar volume at s.t.p.
At s.t.p., 1 mole of gas occupies 22.4 litres. ext{Thus, for } 0.2 ext{ moles of} N₂O, we calculate:
ext{Volume} = 0.2 ext{ moles} imes 22.4 ext{ litres/mole} = 4.48 ext{ litres}.