Question

What is the molecular, ionic complete and ionic net equation for the double displacement reaction between Ca(NO₃)_2(aq) + Na₂CO_3(aq)?

Answer 1

Molecular equation:

In molecular equation, compounds reacting are shown by their chemical formulas only. There is no representation of ions in the equation.

Molecular equation is just a balanced chemical equation.

(PART A)

MOLECULAR EQUATION OF REACTION BETWEEN CALCIUM NITRATE & SODIUM CARBONATE :

When calcium nitrate reacts with sodium carbonate, calcium carbonate and sodium nitrate are formed as products. This is an example of double displacement reaction.

So, reaction will be written as:

For balancing the equation we'll put 2 as stochiometric coffficient to sodium nitrate:

(Molecular equation) (Calcium carbonate, insoluble in water is formed as precipitate in reaction)

Complete ionic equation: In this type of equation, molecular species are represented as respective ions i.e.

Ca(NO₃)₂ will be written as Ca^{​​​​​2+} & NO^{​​​​​}_​​3^{​ -}

^{Compounds that are dissociated and are soluble in water (medium of reaction) are only represented by their ions in complete ionic equation. If there is formation of precipitate in reaction, it's written in molecular formula only.}

(PART B)

IONIC COMPLETE EQUATION OF REACTION BETWEEN CALCIUM NITRATE & SODIUM CARBONATE :

Calcium carbonate is insoluble water, formed as precipitate during reaction, hence written as molecular formula only.

Net ionic equation:

While writing net ionic equation we cancel species present on both sides of reaction so as to get net ionic equation.

(PART C)

NET IONIC EQUATION OF REACTION BETWEEN CALCIUM NITRATE AND SODIUM CARBONATE:

~ Na+ & CO​​​​​3​​​​​​​-2 species being present on both sides of reaction are cancelled while writing net ionic equation.