Which reaction below is a physical change? a. CH4(g) + 2O2(g) → CO2(g) + 2HsO(l)
B. CaO(s) + H2O(l)→ Ca(OH)2(s)
c. H2O (l) → H2O(s)
d. 2HsO (l) → 2H2(g) + O2(l)

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?

This drawing shows a human body system. what is the primary function of this body system?

What type of chemical reaction occurs between silver nitrate (agno3) and copper (cu)? the equation i was given is 2agno3 + cu —> 2ag+ cu(no3)2.