Periodic Table Review

The isotope Cobalt-60 contains:

• 60 protons and 27 neutrons

• 60 neutrons and 27 protons

• 33 neutrons and 27 protons

• 33 protons and 27 neutrons

How do the three isotopes Sn-116, Sn-118, and Sn-119 differ?

• Sn-116 has 166 neutrons, Sn-118 has 168 neutrons, and Sn-119 has 169 neutrons

• Sn-116 has 116 neutrons, Sn-118 has 118 neutrons, and Sn-119 has 119 neutrons

• Sn-116 has 66 neutrons, Sn-118 has 68 neutrons, and Sn-119 has 69 neutrons

• Sn-116 has 50 neutrons, Sn-118 has 52 neutrons, and Sn-119 has 53 neutrons

Which of the following distinguishes isotope Uranium-235 from Uranium-238?

• Number of neutrons in the nucleus

• Location on the periodic table

• Amount of negative charge

• Ability to form ions

How many valence electrons are in a neutral atom of nitrogen (N)?

• 2

• 3

• 5

• 15

Which of these gaseous elements is LEAST reactive?

• hydrogen

• helium

• nitrogen

• oxygen

The alkaline earth metal elements are in the same family in the periodic table because they all have

• one valence electron.

• two valence electrons.

• seven valence electrons.

• eight valence electrons.

Carbon has a significant role in the chemistry of living organisms because it tends to form four bonds with other atoms. Which BEST explains the ability of carbon to form these bonds?

• 4 valence protons

• 4 valence electrons

• 6 total protons

• 6 total electrons

The position of an element on the periodic table helps scientists predict the number of electrons an atom will gain or lose during ion formation. According to the Periodic Table of Elements, which element is most likely to gain two electrons when it forms an ion?

• Calcium (Ca)

• Mercury (Hg)

• Oxygen (O)

• Iodine (I)

What is the charge of Chlorine (Cl) if it gains 1 electron?

• +1

• -1

• +7

• 0

Which best represents how electrons are arranged in the energy levels of a carbon atom?

• first energy level = 1 electron, second energy level = 5 electrons

• first energy level = 2 electrons, second energy level = 4 electrons

• first energy level = 3 electrons, second energy level = 3 electrons

• first energy level = 4 electrons, second energy level = 2 electrons