Joseph Priestley was the first to report the discovery of which element and…

Concept

In the history of chemistry, discovery credit depends on preparing or isolating a substance, observing its distinctive properties, and communicating the result. Credit may be shared when preparation, recognition, and publication occurred at different times.

Application

1. On 1 August 1774, Joseph Priestley heated mercuric oxide with focused sunlight and collected the gas released.

2. He observed that a candle burned much more brightly in this gas and that it supported breathing unusually well. The gas was later named oxygen.

3. Therefore, the element described in the question is oxygen.

Contrast and cross-check

• Neon and krypton were isolated by William Ramsay and Morris Travers in 1898, while helium was first detected in the solar spectrum in 1868 and isolated on Earth in 1895.

• The Royal Society of Chemistry records that Priestley made oxygen in 1774 and was the first to publish an account; the American Chemical Society independently identifies his 1774 discovery of oxygen.

Result: Oxygen.