Periodic Table & Atomic Structure

How many neutrons are in an atom of chlorine?

• 17

• 18

• 34

• 35

How many electrons are in an neutral atom of sodium?

• 22

• 23

• 11

• 12

Which is the correct number of valence electrons in the element Sulfur (S)?

• 16

• 6

• 2

• 4

Which of these elements has 5 valence electrons?

• Boron (B)

• Rubidium (Rb)

• Vanadium (V)

• Arsenic (As)

Which is the halogen that is in Period 5?

• Bromine (Br)

• Iodine (I)

• Strontium (Sr)

• Xenon (Xe)

Which metalloid is in the fourth period and the same group as Carbon?

• Silicon

• Tin

• Germanium

• Boron

Identify the representative elements from the list

• Na, Ca, Si

• Co, Ni, Sc

• U, Re, Sn

• Pt, Pd, Ag

An element has similar chemical properties as oxygen and selenium. It has an atomic number greater than krypton but less than iodine. Use the periodic table to identify the element.

• Te

• Br

• Se

• i

The modern periodic table is arranged by increasing atomic mass of the elements.

• True

• False

In a neutral atom, the number of protons is equal to the number of neutrons.

• True

• False