JEE MainChemistrys Block Elements
Which of the following statements is correct regarding the thermal decomposition of lithium nitrate and sodium nitrate?
Options
- ALithium nitrate evolves a mixture of two gases, while sodium nitrate evolves only one gas.
- BBoth nitrates release a brown gas upon heating.
- CBoth nitrates leave behind a solid metal oxide as the residue.
- DLithium nitrate releases only one gas upon heating.
Correct answer
A. Lithium nitrate evolves a mixture of two gases, while sodium nitrate evolves only one gas.
Step-by-step solution
The thermal decomposition of lithium nitrate and sodium nitrate proceeds as follows: 4 LiNO ₃ 2 Li ₂ O + 4 NO ₂ + O ₂ 2 NaNO ₃ 2 NaNO ₂ + O ₂ Lithium nitrate evolves a mixture of two gases ( NO ₂ which is a brown gas, and O ₂ ), whereas sodium nitrate evolves only one gas ( O ₂ ). Also, lithium nitrate leaves behind a metal oxide ( Li ₂ O ), while sodium nitrate leaves behind a metal nitrite ( NaNO ₂ ). Thus, the statement that lithium nitrate evolves a mixture of two gases, while sodium nitrate evolves only one ga