This question is about gases in the atmosphere and the laboratory preparation of oxygen.
Which is the most abundant gas in dry air? A. argon B. carbon dioxide C. nitrogen D. oxygen
Which gas makes up approximately 0.9% of dry air? A. argon B. carbon dioxide C. nitrogen D. oxygen
A piece of clean copper foil is heated strongly in air. State the formula and colour of the solid compound formed.
Oxygen gas can be prepared in the laboratory by adding a liquid dropwise from a tap funnel into a conical flask containing a solid catalyst, and collecting the gas over water.
The liquid in the tap funnel is: A. dilute nitric acid B. hydrogen peroxide solution C. water D. dilute hydrochloric acid
The catalyst solid in the conical flask is: A. copper(II) sulfate B. iron filings C. manganese(IV) oxide D. sodium chloride
Suggest another apparatus that can be used to collect the oxygen gas instead of collecting it over water.
Complete the equation for the catalytic decomposition of hydrogen peroxide by inserting the missing state symbols:
2H2O2(...)→2H2O(...)+O2(...) 2\text{H}_2\text{O}_2(\text{...}) \rightarrow 2\text{H}_2\text{O}(\text{...}) + \text{O}_2(\text{...}) 2H2O2(...)→2H2O(...)+O2(...)Describe the test used to identify carbon dioxide gas and state the expected observation.
