Question

Answer the questions about the following reaction.

4Al(s) + 302(g) → 2A1203 (s)
How many molecules of O2 are used in the reaction?
How many oxygen atoms are required?
How many moles of Al2O3 are formed?
What is the mole ratio of Al to O?

Answer 1

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

Step-by-step 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

For 1: The number of oxygen gas molecules used in the reaction are
`1.807* 10^(24)`

For 2: The number of oxygen gas molecules used in the reaction are
`3.613* 10^(24)`

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

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

Step-by-step 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* 10^(23)` number of molecules

So, 3 moles of oxygen gas will contain
`(3* 6.022* 10^(23))=1.807* 10^(24)` number of molecules.

Hence, the number of oxygen gas molecules used in the reaction are
`1.807* 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* 10^(23)` number of atoms

So, 3 moles of oxygen gas will contain
`(2* 3* 6.022* 10^(23))=3.613* 10^(24)` number of oxygen atoms.

Hence, the number of oxygen gas molecules used in the reaction are
`3.613* 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