Semester Review

A phosphorous isotope consists of 15 protons, 15 electrons, and 16 neutrons. What is its mass number?

• 30

• 15

• 31

• 46

What is an orbital?

• region of an atom that contains the protons and neutrons; also called the nucleus

• A 3D region around the nucleus that indicates the probable location of an electron

• The number of protons and neutrons in the nucleus of an atom

• The electrons in the outermost energy level or shell, of an atom

Atoms of the same element may have different mass numbers.

• True

• False

Which atomic particle has about the same mass as a neutron but has a positive electrical charge?

• neutron

• electron

• proton

• orbital

Refer to the periodic table. Which element has the highest electronegativity?

• carbon

• lithium

• fluorine

• oxygen

Which element is most similar in behavior to lithium?

• calcium

• magnesium

• chlorine

• sodium

How many valence electrons does sulfur have?

• 2

• 4

• 6

• 8

What is ionization energy?

• the energy required to move an electron from an atom

• measure of the attraction that an atom has for the electrons it shares in a molecule

• half the distance between the nuclei of identical atoms that are bonded together

• same thing as electron configuration

Electronegativity generally ______________ across a period and _________down a group.

• increases, decreases

• decreases, increases

• stays the same, decreases

• increases, stays the same

Ionization energy generally ________ as you go across the PT from left to right.

• stays the same

• decreases

• increases

• fluctuates wildly