Answer:
1. earth metal 2. halogen 3.The elements are arranged in seven horizontal rows, called periods or series, and 18 vertical columns, called groups. ... Elements in the periodic table are organized according to their properties.
Inventor: Dmitri Mendeleev please name most brainliest
Because they are coming from the ground and always safe
The given balanced reaction is,

The stoichiometric coefficients of each element or compound represents the number of moles of that element or compound required for the complete reaction to take place.
The mole ratios of different products and reactants will be:



So the mole ratio comparing iron (Fe) and oxygen gas (
) is
4 : 3
Answer:
Inside the nucleus, the attractive strong nuclear force between protons outweighs the repulsive electromagnetic force and keeps the nucleus stable. Outside the nucleus, the electromagnetic force is stronger and protons repel each other.
Explanation: