Bonding, Naming, and Formulas

What are valance electrons?

• an outer shell electron that is associated with an atom that is responsible for the chemical properties of the atom

• a positive charge

• an atom

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

Where are nonmetals located on the periodic table?

• Upper left corner

• Left hand side and in the middle

• Only on the left

• Upper right hand corner (triangle) above metalloids

When should prefixes be used in the name of a compound?

• When the elements are all metals

• When the elements are all nonmetals

• When the elements are metals and nonmetals

What do the prefixes in a compound name represent?

• The number of atoms of an element in a formula

• The charges of the ions

• The number of ions in a formula

Which prefix should be used with this atom: N₇

• tetra

• penta

• nona

• hepta

When should the charges of an ion be found to determine the formula of a compound?

• When the elements are all metals

• When the elements are all nonmetals

• When the elements are metals and nonmetals

Ionic compounds are written with

• cation (+ ion) first then anion (- ion)
• anion (- ion) first then cation (+ ion)
• either way is fine
• polyatomic ions first

In an ionic compound the charges must add up to zero. To achieve this, they bond in set ratios. We can check this by multiplying the charges of each ion by each other to find the number of each ion needed in the subscripts. This is known as the criss cross method.

• True

• False

Which of the following equations shows the criss cross method used correctly?

• (+1)x + (-1)y: NaCl₂

• (+3)x + (-2)y: Al₂S₃

• (+2)x + (-2)y: NaS

• (+2)x + (-1)y: CaF

Tags

NGSS.MS-PS1-1

True or false: When naming ionic compounds (metal and nonmetal), use prefixes to indicate subscripts

• True

• False