Which of the following oxides can be reduced by hydrogen?
Aluminium oxide
Magnesium oxide
Sodium oxide
Silver oxide
Correct answer is D
Considering the electrochemical series, we can say that hydrogen can reduce only oxides of copper, mercury, silver, and gold as these metals are less reactive than hydrogen. The reduction of oxides of tin, iron, zinc, magnesium, calcium, and potassium is not possible by hydrogen as these metals are more reactive than hydrogen
CH3COOONa
Mg(OH)Cl
NaHSO4
(NH4)2SO4
Correct answer is C
Acidic Salt: A normal salt which is formed by the neutralization of a strong acid and weak base is called acidic salt
The reaction was slowed down
All the dilute HCl has reacted
All the Mg has reacted
Hydrogen gas is produced at a steady rate
Correct answer is C
No explanation has been provided for this answer.
Both large
Both negligible
Constant and negligible
Large and negligible
Correct answer is D
In a gas, the distance between molecules, whether monatomic or polyatomic, is very large compared with the size of the molecules; thus gases have a low density and are highly compressible.
Cohesive Force is negligible in case of gases.
When a reaction is endothermic,
Enthalpy change, \(\Delta\)H is negative
Heat content of a product is less than the heat content of a reactant
Heat content of reactants is less than the heat content of product
The reaction is non-spontaneous
Correct answer is C
An endothermic reaction is any chemical reaction that absorbs heat from its environment. The absorbed energy provides the activation energy for the reaction to occur.
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