Question 5 is the second one.
Answer: i think its A diatomic compound..
Explanation: hope i helped! sorry if im wrong!
Answer: Calcium Sulphate Hemihydrate
The compound of calcium which is used for plastering of fractured bones is Plaster of Paris. It is also called as Calcium Sulphate Hemihydrate.
Answer: 1. 0.045moles
2. 2.10 grams
Explanation:
According to avogadro's law, 1 mole of every substance occupies 22.4 L at STP and contains avogadro's number
of particles.
To calculate the moles, we use the equation:
1. 
2. Mass of 