| # | Clue | Answer As Given | Value | Round | Category | Air Date | Show |
|---|---|---|---|---|---|---|---|
| Though at least 95% of the atmosphere of Venus is this gas, there are no plans yet for a Venus cola | carbon dioxide | $400 | DJ | THE SOLAR SYSTEM | 1988-09-23 | #930 | |
| The greenhouse effect that traps heat is produced by a layer of this gas in the atmosphere | carbon dioxide | $200 | DJ | PLANET EARTH | 1988-05-09 | #861 | |
| A space module's life support system must remove this gas, a primary product of respiration | carbon dioxide | $800 | DJ | MAN IN SPACE | 1987-11-25 | #743 |