2nd Quarter Science Review Grade 9

Valence electrons are the:

• number of electrons lost

• number of electrons gained

• electrons in the innermost energy level of an atom

• electrons in the outermost energy level of an atom

which pair of an elements can combine to form ionic bonds?

• H and Cl

• H and N

• S and Sr

• Xe and F

A strontium atom differs from a strontium ion in a way that the atom has a greater:

• atomic number

• mass number

• number of electrons

• number of protons

What is the bond formed when an atom transfers an electron/s?

• covalent

• ionic

• dative

• mettalic

A positive ion is known as a/an:

• cation

• anion

• electron

• proton

which bond is formed when electrons are equally shared between two atoms?

• ionic

• covalent

• mettalic

• anion

What type of formula is based on the actual number of atoms that comprise a molecule of that compound?

• empirical formula

• Lewis electron-dot structure

• structural formula

• molecular formula

Which of the following compounds does not contain a polyatomic ion?

• potassium nitrate

• calcium sulfite

• potassium nitrite

• potassium nitride

What is the molecular/chemical formula for heptane?

C_nH_2n+2

• C₇H₁₂

• C₇H₁₆

• C₆H₁₂

• C₆H₁₄

What is the smallest member of the alkene family?

• methene

• ethene

• propene

• butene