Science 9 - Chemistry Review

A valence electron....

• is a core electron

• is the same as the number of protons

• is an electron in the outer shell

• is the same as the number of neutrons

Ionic compounds are usually made of

• Two metals

• A metal and non-metal

• Two non-metals

Covalent compounds are made of

• Two metals

• A metal and a non-metal

• Two non-metals

What is the formula for dicarbon tetrahydride?

• C2H2

• CH4

• C2H4

• C3H6

Which of the following is the correct formula for Magnesium Bromide?

• MGBR

• MgBr

• Mg2Br

• MgBr2

Which of the following is a property of halogens? (select all that apply)

• They are toxic

• They are somewhat reactive

• They are very reactive

• They are all solids

Which of the following is usually a property of metals? (select all that apply)

• They are good conductors of heat and electricity

• They are often gases at room temperature

• They are brittle

• They are shiny

Why are alkali metals like sodium and potassium so reactive?

• That's just how they are. Don't worry about it

• They have 7 valence electrons and only need one more to form an octet

• They have 1 valence electron and only need to lose one to have an octet

• They are metals and all metals are very reactive

What is the quickest way to determine the number of valence electrons in an atom

• Draw the Bohr diagram

• Look at the element's symbol

• Look at the row it is in

• Look at the column it is in

The following is a Bohr model for Nickel. Based on this, what is the mass of a Nickel atom?

• 59

• 28

• 31

• 3