They become more stable because they achieve a full outer shell of valence electrons with the magic number of 8.
Answer : The molecule of ethane present in 64.28 L of ethane gas at STP is, 
molecule.
Solution :
At STP,
22.4 L volume of ethane present in 1 mole of ethane gas
64.28 L volume of ethane present in 
of ethane gas
And, as we know that
1 mole of ethane molecule contains 
molecules of ethane
2.869 moles of ethane molecule contains 
molecules of ethane
Therefore, the molecule of ethane present in 64.28 L of ethane gas at STP is, molecule.
23. The correct answer would be a (AlPO4 + H2O).
This is an example of a neutralization reaction (an acid and a base react to form water and a salt).
24. a, combination reaction. There are two reactants and one product.
C - Identify the element because each element has it’s own spectra light , which are released when electrons return to ground state
Because it’s possible for the book to fall but it’s not yet falling if u understand
