Question

05) Teacher wrote the electronic configuration of an atom of an element as 2, 8, 7. What is the atomic number of
?
ਅਧਿਆਪਕ ਨੇ ਕਿਸੇ ਤੱਤ ਦੋ ਪਰਮਾਣੂ ਦੀ ਇਲੈਕਟ੍ਰਾਨੀ ਤਰਤੀਬ 2, 8, 7 ਲਿਖੀ। ਇਸ ਤੱਤ ਦਾ ਪਰਮਾਣੂ नववी?
?
(B)2
(C) 17
(D)
06) Sanjeev asked his teacher that which law is obeved from these options to balance a chemical equation?​

Answer 1

Answer:

5. 17

6. law of conservation of mass

Answer 2

Answer:

Electronic configuration gives the distribution of atoms of an element in its different shells.

For example : if an element has an atomic number as 10 then its diistribution will be like 2, 8 where 2 atoms will be in K shell while 8 atoms will be in L shell.

Explanation:

Here the configuration is 2,8,7 so the atomic number will be 2+8+7=17 where 2 atoms will be K shell, 8 will be in L shell and 7 atoms in M shell.

The law which can be obeserved from this is Law of conservation of mass which states that mass can neither be created nor be destroyed.

Product of reactants = Product of products