Question

calculate the number of aluminium ions present in 0.051 g of aluminium oxide . ( atomic mass of Al =27u)​

Answer 1

Step-by-step explanation:

Hint: The mass of an ion is the same as that of an atom of the same element. Atomic mass of Al = 27 u) . The number of aluminium ions (Al3+) present in one molecule of aluminium oxide is 2.

Answer 2

Answer:

mole of Al2O3=2×27+3×16

                     =102g

Moles of Al2O3=1020.051=5×10−4 moles

1 mole contains 6.02×1023molecules

∴5×10−4g of Al2O3 contains = 5×10−4×6.02×1023=3.011×1020 molecule 

no. of Al3+ ions in 1 molecules of Al2O3 is 2.

∴ No. of aluminium ions will be:-

2×3.011×1020=6.022×1020.

Answered By

anannya