Chapter 3.9, Problem 1PE

(a)

Interpretation Introduction

Interpretation:

The amount of ${\text{Al}}_{\text{2}}{\text{O}}_{\text{3}}$ formed in the given reaction has to be determined.

Concept Introduction:

Molar mass:

• Molar mass of a molecule can be calculated from its molecular formula by taking the sum of atomic masses of all the elements present in it.
• Conversion formula for number moles into mass of a molecule,

$Massingrams=Numberofmoles\times Molarmass$ 

(b)

Interpretation Introduction

Interpretation:

The amount of excess reactant left at the end of reaction has to be determined.

Concept Introduction:

• Limiting reactant is defined as a reactant which is totally utilized in a chemical reaction and decides when the reaction stops.
• Excess reactant is defined as a reactant which is not totally utilized in a chemical reaction and left some of it without utilizing in reaction.
• Molar mass of a molecule can be calculated from its molecular formula by taking the sum of atomic masses of all the elements present in it.
• Conversion formula for number moles into mass of a molecule,

$Massingrams=Numberofmoles\times Molarmass$