How to find net force
The net force is the vector sum of all forces act upon an object.
The formula to calculate net force is Fnet = ma
where the net force is equal to the mass of an object (in Kg) multiplied by the acceleration of the object (in meters per second squared)
You may also calculate the net force acting upon an object with Fnet = Fa + Ff
where the net force is equal to the sum of the applied force and the force of friction.
hope that helped
Atomic number is same as the number of protons in the element which is further equal to the number of electrons. As the number of electrons increases in the element, the atomic number of the element also increases.
In periodic table, elements are arranged in the groups, and these groups are columns starting from 1 to 18, elements are arranged in increasing order of atomic number. Elements are placed with difference of one atomic number.
First four elements present in the periodic table is:
atomic number is one (1).
atomic number is two (2).
atomic number is three (3).
atomic number is four (4).
Thus, the series of atomic numbers that represents the ordering of consecutive elements within the periodic table is the last option - 1, 2, 3, 4...
Fluorine(F)
Explanation:-
- Fluorine has Z=9
- +2 charge means 2 electrons donated (7left only)
Lets look at Electronic configuration

There are eight bonded electrons in this molecule! :)
2H₂₍g₎ + O₂ ₍g₎→ 2H₂O
138 mol H₂ × (2 mol H₂O ÷ 2 mol H₂)= 138 mol H₂O
64 mol O₂ × (2 mol H₂O ÷ 1 mol O₂)= 128 mol H₂O
128 mol H₂O