Science please help!!

Question

CaO + H₂O ----> Ca²⁺ +2 OH

 

Chemical formula for reactant which gives up a hydrogen ion in this reaction?

 

Chemical formula for the reactant which accepts a hydrogen ion in this reaction?

 

Chemical formula for the reactant which behaves like an acid in this reaction? 

 

Chemical formula for the reactant which behaves like a base in this reaction? 

 

Is this aqueous solution an acid or a base? How do you know ? 

 

Would the pH of this solution be higher than 7 or lower than 7? 

 

The chemical equation for this question is reversible. What does is mean to say that a chemical equation is reversible? Then rewrite the chemical equation to show that it is reversible. 

 

Answer 1

The first step is to understand what is really happening in this equation:

CaO + H₂O ----> Ca²⁺ +2 OH

 

• CaO is dissociating into Ca²⁺ + O^2-
• H₂O is dissociating into H⁺ + OH^-
• After all of the dissociation fun occurs, Ca2+ stays just like that, and the H and O will get together to form another OH^- for a total of 2OH^-

Chemical formula for reactant which gives up a hydrogen ion in this reaction?
H₂O --> OH^- + H⁺  Therefore it is water molecule that acts as a Hydrogen Ion Donor.

Chemical formula for the reactant which accepts a hydrogen ion in this reaction?

CaO --> Ca²⁺(aq) + O^2-(aq)  Calcium Oxide will dissociate when dissolved in water into a calcium and an oxide ion.

During this time, it will accept the H+ released from the ionization of water and form

CaOH(aq) when written out in ionic form is Ca²⁺(aq)+ 2OH-(aq)

Therefore the reactant that accepts the Hydrogen ion in this reaction is CaO

Chemical formula for the reactant which behaves like an acid in this reaction?

Acids Lose/Donate H+ ions...  so which original reactant, CaO or H₂O best fit's this description/definition?

Chemical formula for the reactant which behaves like a base in this reaction? Bases accept/gain H+ions... so which original reactant, CaO or H₂O best fit's this description/definition?

Is this aqueous solution an acid or a base? How do you know ? Acidic solutions have more H+ ions losely floating around in comparison to the OH- ions, bases have more OH-ions than H+ ions, and neutral solutions have equal concentrations of H+ and OH- ions.  Looking at your products, which type of solution is this, acid or base?

 

Would the pH of this solution be higher than 7 or lower than 7? Once you identified this solution as acidic or basic, you could indicate whether the pH is higher than 7 (basic) or lower than 7 (acidic)

The chemical equation for this question is reversible. What does is mean to say that a chemical equation is reversible? Then rewrite the chemical equation to show that it is reversible.

This means that the equation can actually undo itself.  Since this is a physical change (making a solution), the process can be reversed.  Just re-write the equation, but backwards.... or.... show a double arrow ↔ instead of a single arrow.