Who developed the first periodic table?

• Dimitri Mendeleev

• Albert Einstein

• Marie Curie

• Nikola Tesla

Elements in the same column of the periodic table have the same number of ______________.

• neutrons

• atoms

• valence electrons

• protons

Which group contains the most reactive metals?

• alkali metals

• transition metals

• post-transition metals

• noble gas metals

Noble Gases are the least reactive elements.

• True

• False

What two elements make up water?

• Oxygen and helium

• Oxygen and hydrogen

• Water is only made of one element

• Carbon and oxygen

Tags

NGSS.MS-PS1-1

Any element with an atomic number above 92 is man-made and only has radioactive isotopes.

• True

• False

Water is non-polar.

• True

• False

Molecules that are non-polar are symmetrical.

• True

• False

Electrons in the outer energy level of an atom are called valence electrons.

• True

• False

What is a covalent bond?

• When electrons are shared but shared unequally.

• Two atoms share one or more pairs of outer-shell electrons.

• When electrons are shared in a sea of electrons among atoms.

• When two atoms bond when one or more electrons are given to one atom by another atom.

Tags

NGSS.HS-PS1-1