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Here is the link to a great video that explains your question nicely, hope this helps.
When considering atomic orbitals the only important information they really wanted to know is the size of the orbit, which was described by using quantum numbers.
Answer:
NH₃ (Option A)
Explanation:
Arrhenius theory explained that the acids are the ones that have H⁺, either H in its formula. Following this, the bases are the ones that have OH⁻ , either OH and its formula.
It can be used only with compounds with H, or OH.
So the ammonia is not a base, as Arrhenius theory.
It is known that ammonia behaves as a weak base, but it does not have hydroxide ions that can yield to water
Answer: 1. The empirical formula is
2. The molecular formula is 
Explanation:
If percentage are given then we are taking total mass is 100 grams.
So, the mass of each element is equal to the percentage given.
Mass of P = 37.32 g
Mass of N = 16.88 g
Mass of F = 45.79 g
Step 1 : convert given masses into moles.
Moles of P =
Moles of N =
Moles of F =
Step 2 : For the mole ratio, divide each value of moles by the smallest number of moles calculated.
For P = 
For N = 
For F =
The ratio of P: N: F= 1: 1: 2
Hence the empirical formula is 
The empirical weight of
= 1(31)+1(14)+2(19)= 82.98 g.
The molecular weight = 82.98 g/mole
Now we have to calculate the molecular formula.

The molecular formula will be=