What's up ? ! ? You should know most of these.
RbOH is a base because its PH is greater than 7.
Sulfur trioxide is SO₃ .
Mixtures B, C, and D can be separated by distillation.
Pebbles and sand can't.
If some salt is dissolved in a beaker of water, then
the salt is the solute and the water is the solvent.
The equation is not balanced because the number of atoms
of each element on the left is not equal to the number of atoms
of that element on the right.
In fact, the total number of all atoms on the left (8) is not even
equal to the total number of all atoms on the right (10).