Friday, September 30, 2016

Provide the net ionic equation and complete ionic equation for 2Ca + 4H2O -> 2Ca(OH)2 + 2H2

The given equation represents the reaction between calcium and water to generate calcium hydroxide. In this reaction, calcium is in a solid state, while water is in a gas phase, calcium hydroxide is aqueous and hydrogen is in a gaseous state. Incorporating all the states in the equation and writing a well-balanced equation, we get:


`Ca (s) + 2H_2O (g) -> Ca(OH)_2 (aq) + H_2 (g)`


Among the given species only calcium hydroxide ionizes; all...

The given equation represents the reaction between calcium and water to generate calcium hydroxide. In this reaction, calcium is in a solid state, while water is in a gas phase, calcium hydroxide is aqueous and hydrogen is in a gaseous state. Incorporating all the states in the equation and writing a well-balanced equation, we get:


`Ca (s) + 2H_2O (g) -> Ca(OH)_2 (aq) + H_2 (g)`


Among the given species only calcium hydroxide ionizes; all other species will not. Calcium hydroxide ionizes into a calcium ion and a hydroxide ion. 


In other words,  


`Ca(OH)_2 (aq) -> Ca^(2+) (aq) + 2 OH^(-) (aq)`


Substituting this equation in the given equation, we get:


`Ca(s) + 2H_2O (g) -> Ca^(2+) (aq) + 2OH^(-) (aq) + H_2 (g)`


This is the complete ionic equation for the given reaction. 


To get the net ionic equation, we have to cancel out the species that are present on both the reactant and product side. In this case, there are no such species and hence the complete ionic equation is the same as the net ionic equation.


Hope this helps. 

No comments:

Post a Comment