An oxide of a metal which is very low in reactivity series, is heated in a test tube.
A colourless gas is liberated which makes a glowing splinter (like lighted incense stick)
burn brightly. Identify is the oxide and the gas liberated?
ill give 25 points for this one its an emergency....
Answers
Answer:
Ag2o3 is oxide
gas is oxygen
The given metal oxide is silver oxide (Ag₂O), and the gas liberated is oxygen (O₂).
• If we look at the hints given in the question, the first clue is to think of a metal which is placed almost at the bottommost position in the reactivity series. Therefore, mercury, silver, gold are the names that come to the mind as they are the bottom three elements in the reactivity series.
• Now, if we consider any one of these metals, say silver, the oxide of silver is silver oxide (Ag₂O). We know that the oxides of elements placed below hydrogen in the reactivity series are easily decomposed into their respective metal and oxygen by heat.
• The decomposition reaction of Ag2O can be shown as :
2Ag₂O → 4Ag + O₂
• Burning of Ag₂O evolves oxygen, and the second clue in the question also confirms that the gas liberated is oxygen, as it is a characteristic property of oxygen to make a burning splinter glow brightly.
• Therefore, the required metal and the gas liberated are concluded to be silver and oxygen respectively.
Note - The oxides of mercury or gold would also give same results on heating.