Question

Calculate the number of aluminium ions present in 0.051 g. Of aluminium oxide

Answer 1

The number of aluminium ions (Al3+) present in one molecule of aluminium oxide is 2. 1 mole of any pure substance contains Avogrado's number of molecules, that is 6.023x10^23.

Answer 2

Answer:

the mass of Aluminum Oxide = 0.051 g.

The molecular mass of Aluminium Oxide = 2 x mass of Aluminium + 3 x mass of Oxygen.

                                                                 = 2 x 27 + 3 x 16

                                                                 = 102 g

Number of Moles of Aluminium Oxide :

\frac{0.051}{102}=0.0005\:moles

Now, Since 1 mole of Aluminium Oxide contain 2 moles of Aluminium ion,

The Number of Moles of Aluminium ion = 2 x number of moles of Aluminium Oxide  

                                                              =  2 x 0.0005

                                                              = 0.001 moles.

Now, As the number of ion in 1 mole = 6.022\times10^{23}  ions.

The number of ions in 0.001 moles of Aluminium ion = 0.001\times6.022\times10^{23} ions

                                                                                   = 6.022\times10^{20} ions.

Hence there are 6.022\times10^{20} Aluminium ions in 0.051 g of aluminium oxide.

Explanation: