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Answer:
Na is the element from the second period that has the largest atomic radius
Explanation:
The atomic radius is a chemist property from the periodic table. It is decreased when we move in a period from the periodic, so the element in the second period that has the largest radius is Na, and the shortest, the Ar
The atomic radius indicates the distance between the nucleus and the outermost valence layer. In the periods it decreases with increasing Atomic Number, to the right, due to the attraction that the nucleus exerts on the electrons of the outermost orbitals, thus decreasing the core-electron distance.
Answer is: 4) The same subscripts are on each side of the equation.
For example, balanced chemical reaction:
2Mg + O₂ → 2MgO.
1) The same number of atoms is on each side of the equation: two magnesium atoms and two oxgen atoms.
2) The formulas for all substances are correct: in magnesium oxide (MgO), magnesium has oxidation number +2 and oxygen -2, so formula is good, because compound must be neutral.
3) The same mass is represented on each side of the equation: because there is same number of atoms, the mass is the same.
4) The same subscripts are on each side of the equation: oxygen does not have same subscripts.