Which of the following is a salt?

a. o2
b. c2h2
c. c6h12o6
d. nacl

Three alkali metals in group 1 are a. calcium, strontium, barium b. boron, aluminum, gallium c. sodium, potassium, rubidium d. fluorine, iodine, chlorine

Which process does not require the presence of a physical substance in order to transfer heat? air in the atmosphere is heated by the ground. this warm air then rises, and cooler air falls. this is an example of what type of process? how is conduction different from radiation?

Measurements that have similar values are: a. usually accurate b. sometimes accurate c. always accurate d. never accurate