Explanation:
Principle Quantum Numbers : It describes the size of the orbital and the energy level. It is represented by n. Where, n = 1,2,3,4....
Azimuthal Quantum Number : It describes the shape of the orbital. It is represented as 'l'. The value of l ranges from 0 to (n-1). For l = 0,1,2,3... the orbitals are s, p, d, f...
s = 1 orbital
p = 3 orbitals
d = 5 orbitals
f = 7 orbitals
For n = 4
l = 0 to (n-1) = 0 to 3 = (4s , 4p , 4d , 4f)
Number of subshells = 4
Number of orbitals = 1 + 3 + 5 + 7 = 16
The maximum number of electrons the n = 4 shell can contain:
Each orbital can holds upto two electrons, then 16 orbitals will have :

32 is the maximum number of electrons the n = 4 shell can contain
Explanation:
The reaction expression is given as;
2H₂
+ O₂
→ 2H₂O
From the balance reaction expression:
2 mole of hydrogen gas combines with 1 mole of oxygen gas on the reactant side;
This produces 2 mole of water on the product side of the expression.
The product is in liquid form.
This reaction is a synthesis reaction because a single product is formed from two reactants.
A gallon of water weighs 8.34 pounds
They all have something to do with electricity