Problem 1: for which of the following activities might you want to hire a chemist?
a. building a garage
b. testing a sample of water from a well
c. finding a comet
d. examining the structure of plant cells
problem 2: which of the following procedures involves a physical change in one of the substances?
a. creating salt by reacting sodium metal and chlorine gas
b. allowing a nail to rust
c. building a model rocket propelled by mixing baking soda and vinegar
d. grinding chalk into a fine powder

Select the correct text in the passage. which sentences describe examples of sustainable living? i live in an old apartment building downtown, but my company is based in an office park on the outskirts of the city. i drive an old car that needs to be replaced. i plan to buy a hybrid for better gas mileage, but for now i am able to carpool with a couple of friends from work. the drive to the office park is about 45 minutes each way, but we do get to work in a modern building. the architects just received a leed certification for the design.

To find the enthalpy of a reaction in the lab, you measured the of the reactants and the change during the reaction.

The number of moles of a given mass of a substance can be found without knowing its molecular formula or molar mass. true false