Carbon: A Central Building Block: Tutorial

Carbon: A Central Building Block: Tutorial

by David Blankenship

Multiple Choice

How many valence electrons does a carbon atom have?

• two

• four

• six

Multiple Choice

How does the carbon atom complete its octet?

• It forms ionic bonds by sharing electrons.

• It forms covalent bonds by donating electrons.

• It forms covalent bonds by sharing electrons.

Multiple Choice

How many pairs of electrons does the carbon atom share with each hydrogen atom in the chemical compound methane, which has the formula CH₄ ?

• one pair

• two pairs

• four pairs

Multiple Choice

A hydrocarbon consists of four carbon atoms with one double bond. Predict the molecular formula of this compound.

• C₄H₈

• C₄H₁₀

• C₄H₄

• C₄H₆

Multiple Choice

Ethane is an alkane having two carbon atoms bound to hydrogen atoms. Recall what you have learned about the tetravalent nature of carbon and predict the chemical formula of this molecule.

• C₂H₄

• C₂H₆

• C₂H₂

Multiple Choice

Identify the chemical compounds.

• methane

• ethyne

• ethene

• cyclopentane

Multiple Choice

Identify the chemical compounds.

• methane

• ethyne

• ethene

• cyclopentane

Multiple Choice

Identify the chemical compounds.

• methane

• ethyne

• ethene

• cyclopentane

Multiple Choice

Identify the chemical compounds.

• methane

• ethyne

• ethene

• cyclopentane

Multiple Choice

Two different hydrocarbon isomers have the same molecular formula. What makes them different?

• Their atoms are physically connected together to form different structures.

• Their molecules contain different numbers of ionic and covalent bonds.

• Their molecules have different numbers of hydrogen atoms.

Multiple Choice

A hydrocarbon of pentane has two isomeric forms—n-pentane and iso-pentane. The molecular formula of the n-pentane is C₅H₁₂. Predict the molecular formula of the iso-pentane.

• C₅H₁₀

• C₅H₁₂

• C₅H₈

Multiple Choice

Butene has two isomers—one with methyl groups on the same side of the double bond and the other with methyl groups on the opposite side. What kind of isomers are these?

• structural isomers

• geometric isomers

• halotropic isomers

Multiple Choice

Predict the chemical formula of butyne, having one carbon-carbon triple bond.

• C₄H₈

• C₄H₁₀

• C₄H₆

Multiple Choice

A molecule of alkene has the chemical formula C₃H₄. How many carbon-carbon double bonds are present in the molecule?

• one

• two

• three