Alberta Chem 20 course review

What would be the proper chemical formula for combining Al³⁺ and Cl^- :

• AlCl₃

• Al₃Cl

• AlCl

• Al₃Cl₃

Answer explanation

The proper chemical formula for combining Al³⁺ and Cl^- is AlCl₃. This formula represents the correct combination of one aluminum ion (Al³⁺) and three chloride ions (Cl^-).

Tags

NGSS.HS-PS1-1

Name the following ionic compound: BeCl₂

• beryllium chlorine

• beryllium II chloride

• beryllium chloride

• beryllium dichloride

Answer explanation

The correct name for the ionic compound BeCl2 is beryllium chloride. It consists of beryllium and chlorine ions.

What is the name of the compound with the formula FePO₄?

• iron phosphate

• iron (II) phosphate

• iron (IV) phosphate

• iron (III) phosphate

Answer explanation

The compound with the formula FePO4 is iron (III) phosphate. It is named so because iron in this compound has a +3 oxidation state.

What is the name of Ca(NO₃)₂

• calcium nitrite

• calcium II nitrate

• calcium nitrate

• carbon nitrate

Answer explanation

The correct name for Ca(NO3)2 is calcium nitrate. It is formed by the combination of calcium and nitrate ions.

Classify: 
sulfur dioxide, SO₂

• ionic compound

• molecular compound

• metallic element

• non-metallic element

Answer explanation

Sulfur dioxide, SO2, is a molecular compound. It consists of two non-metallic elements, sulfur and oxygen.

What's a valence electron?

• electrons in the second energy level

• electrons in the outermost energy level

• the atomic number

• electrons in the first level

Answer explanation

Valence electrons are electrons in the outermost energy level of an atom. They determine the chemical properties and reactivity of an element.

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

What is the best explanation of VSEPR theory?

• It explains the shapes that electrons make around atoms when they repel

• It explains how many electrons fit into an element's valent shell

• It explains why electrons pair up

• It explains why electrons repel each other

Answer explanation

VSEPR theory explains the shapes formed by electrons around atoms when they repel each other.

Which is true of VSEPR theory?

• It explains the origins of the universe

• It describes different molecular shapes

• It is loosely based on the Norse myth of Woden

• It describes which orbital electrons will fill

Answer explanation

VSEPR theory describes different molecular shapes.

What is the VSEPR theory used to predict?

• Bond Strength

• Polarity

• Molecular Shape

• Electronegativity

Answer explanation

The VSEPR theory is used to predict the molecular shape.

Who could this be?

• H₂O

• NH₃

• CO₂

• CH₄

Answer explanation

The correct choice is NH3 because it is the only option that represents ammonia, which is a common compound with the chemical formula NH3.

Tags

NGSS.HS-PS1-3

NGSS.HS-PS1-4

NGSS.HS-PS1-5