They move because of convection currents in the mantle
Water is H2O but I'm not sure about solids.
A covalent bond is formed between two non-metals that have similar electronegativities.
An <em>i</em><em>o</em><em>n</em><em>i</em><em>c</em><em> </em><em>b</em><em>o</em><em>n</em><em>d</em> is formed between a metal and a non-metal. Non-metals(-ve ion) are "stronger" than the metal(+ve ion) and can get electrons very easily from the metal. These two opposite ions attract each other and form the ionic bond.
Answer:
They are similarly charged, which is why they repel each other.
Answer:
RbOH
Explanation:
For this question, we have to remember what is the definition of a base. A base is a compound that has the <u>ability to produce hydroxyl ions</u>
, so:

With this in mind we can write the <u>reaction for each substance:</u>




The only compound that fits with the definition is
, so this is our <u>base</u>.
I hope it helps!