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
Delta enthalpy = 2x386-3x1x432-3x942=-3350kJ/mol
Answer:
B
Explanation:
Oil > Animals > Plants > Chemicals
An atom that has 13 protons and 15 neutrons is isotope of Aluminium (answer C)
<u><em>Explanation</em></u>
- Isotope is a form of the same element with the equal number of protons but difference number of neutrons in their nuclei.
- In other words isotope has the same atomic number but different mass number.
- Atomic number of a element is determined by number of protons of an element.
- from the periodic table Aluminum in atomic number 13 therefore it has 13 protons <em>therefore an atom that has 13 protons and 15 neutrons is a isotope of Aluminium. </em>
Answer: 
Explanation:
According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.
Thus in the reactants, there are 2 atoms of hydrogen and 2 atoms of iodine .Thus there has to be 2 atoms of hydrogen and 2 atoms of iodine in the product as well. Thus a coefficient of 2 is placed in front of HI.
The balanced chemical reaction is:
