Is grinding glass physical or a chemical change

What happens to energy in an open system?

Margaret wants to make an orange flavored drink by stirring powdered drink mix into a glass of water. she doesn't like drinks that have small clumps of powdered solid in them, so she wants the drink to be a perfect solution. what factors should margaret not consider when deciding how much powder to add to her glass of water?

How many grams of co(g) are there in 74.5 ml of the gas at 0.933 atm and 30o c?