1. **Oxide type in excess $O_{2}$:** Li → $Li_{2}O$ (oxide), Na → $Na_{2}$$O_{2}$ (peroxide), K/Rb/Cs → superoxides (K$O_{2}$). Larger cation = larger anion stabilized.
2. **Solvay process trap:** $NaHCO_{3}$ precipitates because it is least soluble — NOT because it forms first.
3. **Li anomaly:** Li resembles Mg (diagonal relationship): normal oxide only, carbonate decomposes, $LiNO_{3}$ gives $Li_{2}O$ + N$O_{2}$ + $O_{2}$, no solid $LiHCO_{3}$.
4. **Be anomaly:** Be resembles Al: both have amphoteric oxides, covalent chlorides, and max covalency of 4.
5. **Plaster of Paris sets by hydration:** $CaSO_{4}$·½$H_{2}O$ + 3/2$H_{2}O$ → $CaSO_{4}$·2$H_{2}O$ (gypsum); exothermic with slight expansion.$
Part of INC-05 — s-Block Elements
s-Block Elements: 5 Must-Know Facts
Want to generate AI summaries of your own documents? NoteTube turns PDFs, videos, and articles into study-ready summaries.
Sign up free to create your own