At all times when a lab is being operated no matter what the circumstances
Aluminum foil I think but if not goodluck :)
Answer : 6.41 moles of silicon are in the sample.
Solution : Given,
Moles of magnesium = 9.62 moles
The given chemical formula for talc is, 
From the given chemical formula we conclude that
The stoichiometry of magnesium and silicon is 3 : 2
3 moles of magnesium is equivalent to 2 moles of silicon
9.62 moles of magnesium will be equivalent to
moles of silicon
Therefore, the number of silicon present in sample are 6.41 moles.
The hydrosphere contains all the water