A chemical occurs when one substance is changed into a
substance with
properties. The new substance takes on a new
with different
from the original substance.

Select each correct answer. more than one answer may be correct. which of the following is a characteristic of unicellular organisms? they can possess tissues and organs. all of their functions are performed by a single cell. they are usually microscopic. each of their cells is specialized to perform a specific function.

Describe the difference between a. a hypothesis and a theory and b. an observation and an experiment.

Achemist has dissolved a certain substance in water. the chemist knows that more of the substance could be dissolved into the water before it stops dissolving. therefore