Humans have used rocks in the creation of tools and building materials true or flase

Ants live on acacia trees in south america. the ants feed on sugars secreted by the trees. the trees provide room for the ants to live. the ants sting any other insect or animal that comes to eat the trees. what type of relationship is this?

If 16.00g of hydrogen gas reacts with 126.73g of oxygen, how many grams of water are yielded? (both reactants are completely consumed in the reaction.)

Which symbol can be used to indicate the pressure at which a chemical reaction is carried out? 25°c 2 atm pa