Question

Answer the questions about the following reaction.

Answer 1

Answer:

1) 1.807 * 10^24 molecules of O2

2) 6 oxygen atoms required

3) There are 2 moles of Al2O3 formed

4)  Mole ratio Al to oxygen =  2/3 = 0.6667

Explanation:

Step 1: The balanced equation

4Al(s) + 302(g) → 2Al203 (s)

We see that we need to consume 4 moles of Aluminium and 3 moles of oxygen to produce 2 moles of Al2O3

How many molecules of O2 are used in the reaction?

we have 3 moles of 02

The number of molecules of 02 in the reaction = 3 moles * 6.022 *10^23 = 1.807 * 10^24 molecules of O2

How many oxygen atoms are required?

Since we have 3 moles of 02 this means there is 3*2 = 6 oxygen atoms required

How many moles of Al2O3 are formed?

There are 2 moles of Al2O3 formed

What is the mole ratio of Al to O?

In the reactant side 4 Al reacts with six oxygen atoms to for two molecules of  Al2O3

Mole ratio Al to oxygen = (No of atoms of Al in  Al2O3)/ (Number of atoms of oxygen in Al2O3)

Mole ratio Al to oxygen =  2/3 = 0.6667

Answer 2

Answer:

For 1: The number of oxygen gas molecules used in the reaction are $1.807\times 10^{24}$

For 2: The number of oxygen gas molecules used in the reaction are $3.613\times 10^{24}$

For 3: The moles of aluminium oxide formed are 2 moles

For 4: The mole ratio of Al : O is 4 : 3

Explanation:

For the given chemical reaction:

$4Al(s)+3O_2(g)\rightarrow 2Al_2O_3(s)$

• For 1:

Moles of oxygen gas reacted = 3 moles

According to mole concept:

1 mole of a compound contains $6.022\times 10^{23}$ number of molecules

So, 3 moles of oxygen gas will contain $(3\times 6.022\times 10^{23})=1.807\times 10^{24}$ number of molecules.

Hence, the number of oxygen gas molecules used in the reaction are $1.807\times 10^{24}$

• For 2:

Moles of oxygen gas reacted = 3 moles

1 mole of oxygen gas contains 2 moles of oxygen atoms.

According to mole concept:

1 mole of a compound contains $6.022\times 10^{23}$ number of atoms

So, 3 moles of oxygen gas will contain $(2\times 3\times 6.022\times 10^{23})=3.613\times 10^{24}$ number of oxygen atoms.

Hence, the number of oxygen gas molecules used in the reaction are $3.613\times 10^{24}$

• For 3:

From the given chemical equation, the moles of aluminium oxide formed are 2 moles

• For 4:

Mole ratio is defined as the ratio of moles of substances present in a chemical reaction. It is also the ratio of stoichiometric ratios in a chemical reaction.

Moles of aluminium reacted = 4

Moles of oxygen gas = 3

Mole ratio of Al : O = 4 : 3

Hence, the mole ratio of Al : O is 4 : 3