Answer:
water was added to powdered rock
Explanation:

The word equation for above chemical equation is :
Sulphur + Oxygen
Sulphur dioxide
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Answer:
temperature
amount
Explanation:
Under the postulate of Boyle's law, both temperature and amount(number of moles) are kept constant.
According to Boyle's law "the volume of a fixed mass of gas varies inversely as the pressure changes if the temperature is constant"
Based on the premise of this law, both temperature and amount of substance is kept constant.