3.1.2 Synthesis and Decomposition Reactions Flashcards
(20 cards)
What is a synthesis reaction?
A synthesis reaction involves the combination of chemical substances to form a larger compound.
What is the general equation for synthesis reactions?
A + B → AB
Can synthesis reactions form simple binary compounds?
Yes, they can form simple binary compounds like AB.
What types of bonds can be formed in synthesis reactions?
Both ionic and covalent bonds can be formed.
Are synthesis reactions typically exothermic or endothermic?
Synthesis reactions are usually exothermic.
Provide an example of a synthesis reaction.
Formation of Ammonia: 3H2(g) + N2(g) → 2NH3(g)
What happens to bonds during the formation of ammonia?
Covalent bonds are formed between nitrogen and hydrogen atoms.
Why is the synthesis reaction of ammonia overall exothermic despite bond breaking?
Because the bonds formed (N–H) are stronger than those broken, releasing more energy.
What is an example of a synthesis reaction involving a metal oxide and water?
CaO(s) + H2O(l) → Ca(OH)2(aq)
What are decomposition reactions?
Decomposition reactions involve the breakdown of a compound into simpler products.
What is the general equation for decomposition reactions?
AB → A + B
What types of bonds can be broken in decomposition reactions?
Both ionic and covalent bonds can be broken.
Are decomposition reactions typically exothermic or endothermic?
Decomposition reactions are endothermic.
Provide an example of a decomposition reaction involving metal carbonates.
CaCO3(s) → CaO(s) + CO2(g)
What energy change occurs in the decomposition of calcium carbonate?
The energy required to break bonds is greater than that released by bonds formed.
What is the electrolysis of water?
2H2O(l) → 2H2(g) + O2(g)
What type of bonds are involved in the electrolysis of water?
The breaking and formation of covalent bonds.
What is photolysis?
Photolysis refers to the decomposition of silver salts into pure silver metal and halogen gas in the presence of light energy.
What is an example of photolysis involving silver chloride?
2AgCl(s) UV light → 2Ag(s) + Cl2(g)
How does photolysis of silver chloride relate to photographic film?
It is the initial step in capturing images through light-sensitive silver halide crystals.
