Why do elements in a group on the periodic table have similar chemical properties?
a. similar atomic masses
b. similar atomic numbers
c. same number of outermost electrons
d. same number of protons

Why should the scientific method be used to answer a question? a. it provides a way to test an idea without any bias. b. it provides a way to test a hypothesis. c. it provides a way to ensure all hypotheses are proven correct. d. it provides a way to quickly turn a hypothesis into a scientific theory.

Which characteristic of water it form droplets? a. low specific heat b. nonpolar structure c. high surface tension d. ability to dissolve substances

Which characteristics can be used to differentiate star systems? check all that apply.