Packet 8: Bonus 5
Answer the following about ions with the element nitrogen. For 10 points each,
[10m] The 2020 Beirut explosion was caused by 2,750 tons of the ammonium salt of this ion. The potassium salt of this ion, called saltpeter, is used in gunpowder and tree stump remover.
ANSWER: nitrate [or NO3-; accept ammonium nitrate or potassium nitrate; reject “nitrite”]
[10e] In the lab, treatment of solutions contaminated with this anion uses alkaline chlorination with bleach. This poisonous ion, present in apple seeds and cherry pits, has formula CN-.
ANSWER: cyanide [accept any answer that ends with cyanide]
[10h] The sodium salt of this anion is used at a concentration of 0.02% as an antimicrobial preservative in laboratory reagents. Upon heating, the sodium salt of this anion rapidly decomposes into sodium metal and pure nitrogen gas.
ANSWER: azide [accept sodium azide]
<Science - Chemistry, Jonathan Ouyang> | VAULT II Packet 08
| Heard | PPB | E % | M % | H % |
|---|---|---|---|---|
| 39 | 19.23 | 97% | 69% | 26% |
Conversion
| Team | Opponent | Part 1 | Part 2 | Part 3 | Total | Parts |
|---|---|---|---|---|---|---|
| Belmont A | Waltham B | 10 | 10 | 0 | 20 | ME |
| Lexington A | Lexington B | 10 | 10 | 10 | 30 | MEH |
| Waltham A | Belmont B | 10 | 10 | 0 | 20 | ME |
Summary
| Tournament | Edition | Match | Heard | PPB | E % | M % | H % |
|---|---|---|---|---|---|---|---|
| VAULT II at Georgia Tech | 2026-01-24 | ✓ | 6 | 20.00 | 100% | 67% | 33% |
| Triangle Cup | 2026-03-13 | ✓ | 1 | 20.00 | 100% | 100% | 0% |
| VAULT II at Eden Prairie HS | 2026-03-13 | ✓ | 3 | 16.67 | 100% | 33% | 33% |
| VAULT II at McGill | 2026-03-13 | ✓ | 4 | 22.50 | 100% | 75% | 50% |
| VAULT II at UCSB | 2026-03-13 | ✓ | 3 | 20.00 | 100% | 67% | 33% |
| VAULT II Northern UK | 2026-04-24 | ✓ | 3 | 16.67 | 100% | 67% | 0% |
| VAULT II Southern UK | 2026-04-24 | ✓ | 4 | 25.00 | 100% | 100% | 50% |
| VAULT II at Harvard | 2026-04-30 | ✓ | 3 | 23.33 | 100% | 100% | 33% |
| VAULT II at MINT | 2026-06-19 | ✓ | 5 | 14.00 | 80% | 60% | 0% |
| VAULT II Stanford Online | 2026-07-17 | ✓ | 7 | 17.14 | 100% | 57% | 14% |