Valence Electrons and Ionic Charges

The video tutorial explains the octet rule, which describes how atoms tend to have a full outer shell of eight valence electrons, leading to chemical stability. It discusses the role of valence electrons in determining chemical properties and how ions are formed by gaining or losing electrons to achieve a noble gas electron configuration. The tutorial also covers the formation of cations and anions, their charges, and how these relate to the periodic table.

What is the primary reason atoms strive to achieve an octet of valence electrons?

• To become more reactive

• To decrease their atomic mass

• To achieve a noble gas configuration

• To increase their atomic number

How can the number of valence electrons be determined for main group elements?

• By the atomic mass

• By the period number

• By the atomic number

• By the last digit of the group number

Which of the following statements is true about transition metals?

• They always have a fixed number of valence electrons

• Their valence electrons can vary depending on bonding

• They have no valence electrons

• Their valence electrons are always equal to their group number

What happens to the size of a sodium atom when it loses an electron to form a cation?

• It remains the same

• It becomes smaller

• It becomes a noble gas

• It becomes larger

Why do metals on the left side of the periodic table form cations?

• They lose electrons

• They share electrons

• They do not form ions

• They gain electrons

What is the charge of a magnesium ion after it loses two electrons?

• -2

• -1

• +2

• +1

How does a chlorine atom achieve a noble gas configuration?

• By losing one electron

• By gaining one electron

• By sharing two electrons

• By gaining two electrons

What is the charge of a chlorine ion after it gains an electron?

• +1

• -1

• +2

• -2

Which group of elements typically forms ions with a -3 charge?

• Group 16

• Group 15

• Group 18

• Group 17

What is the common charge for ions formed by elements in group 16?

• +1

• -2

• -1

• +2