The subscript is the amount of atoms in each molecule and the coefficient is the amount of molecules. there are 4 Hydrogen, 2 Sulfur, and 8 Oxygen in this particular substance.
The trend of atomic radius in the periodic table is increasing from right to left and from top to bottom. In reference to the table, oxygen has smaller radius compared to carbon, which is smaller than aluminum and which is also smaller than potassium. Thus, the trend from smallest to biggest is oxygen carbon, aluminum and potassium.
Ionic solids have high melting points and are rather hard. ... Covalent solids comprise two- or three-dimensional networks of atoms held together by covalent bonds; they tend to be very hard and have high melting points
From the given choices, aluminum oxide is the only ionic
compound there. The ions present are Al3+ and O2-. Aluminum is a
chemical compound of aluminum and oxygen with the chemical formula Al2O3. It is
the most frequently happening of numerous aluminum oxides, and precisely recognized
as aluminum (III) oxide.