$Ca(OH)_2(aq) + 2HNO_3(aq) \rightarrow 2H_2O(l) + Ca(NO_3)_2(aq)$
Is this reaction a:
A. precipitation
B. acid-base neutralization
C. redox reaction
Answer (2)
The given reaction is classified as an acid-base neutralization because it involves calcium hydroxide (a base) reacting with nitric acid (an acid) to produce water and a salt, calcium nitrate. No precipitate forms, and oxidation states remain unchanged, ruling out precipitation and redox classifications. Therefore, the correct answer is acid-base neutralization.
;
The reaction involves C a ( O H ) 2 (a base) and H N O 3 (an acid) reacting to form water and a salt.
No precipitate is formed, so it is not a precipitation reaction.
The oxidation states of all elements remain unchanged, so it is not a redox reaction.
Therefore, the reaction is an a c i d − ba se n e u t r a l i z a t i o n .
Explanation
Understanding the Reaction The given chemical reaction is: C a ( O H ) 2 ( a q ) + 2 H N O 3 ( a q ) → 2 H 2 O ( l ) + C a ( N O 3 ) 2 ( a q ) We need to classify this reaction as precipitation, acid-base neutralization, or redox reaction.
Classifying the Reaction
Precipitation: A precipitation reaction involves the formation of an insoluble solid (precipitate) from the reaction of two aqueous solutions. In this reaction, all reactants and products are in aqueous solution except for water, so no precipitate is formed. Thus, it is not a precipitation reaction.
Acid-Base Neutralization: An acid-base neutralization reaction involves the reaction of an acid and a base to form a salt and water. In this reaction, C a ( O H ) 2 is a base (calcium hydroxide), and H N O 3 is an acid (nitric acid). The products are water ( H 2 O ) and a salt, calcium nitrate ( C a ( N O 3 ) 2 ). Therefore, this is an acid-base neutralization reaction.
Redox Reaction: A redox (reduction-oxidation) reaction involves a change in the oxidation states of the reacting species. Let's examine the oxidation states of the elements in the reaction:
C a in C a ( O H ) 2 : +2
O in C a ( O H ) 2 : -2
H in C a ( O H ) 2 : +1
H in H N O 3 : +1
N in H N O 3 : +5
O in H N O 3 : -2
H in H 2 O : +1
O in H 2 O : -2
C a in C a ( N O 3 ) 2 : +2
N in C a ( N O 3 ) 2 : +5
O in C a ( N O 3 ) 2 : -2
Since the oxidation states of all the elements remain the same throughout the reaction, it is not a redox reaction.
Conclusion Based on the analysis, the reaction is an acid-base neutralization reaction.
Examples
Acid-base neutralization reactions are crucial in many real-world applications. For example, antacids use bases like calcium carbonate or magnesium hydroxide to neutralize excess stomach acid (hydrochloric acid), relieving heartburn and indigestion. Similarly, in wastewater treatment, acidic or alkaline effluents are neutralized before being discharged into the environment to prevent harm to aquatic life and ecosystems. This ensures that the pH levels are within acceptable limits, protecting the environment from the corrosive effects of extreme acidity or alkalinity.
