Four crystalline solids—lithium fluoride (LiF)
CHEMISTRY · Multi-part · A Level · Chemistry · Bonding · Bonding
Problem
Four crystalline solids—lithium fluoride (LiF), potassium bromide (KBr), calcium oxide (CaO), and aluminum oxide (Al₂O₃)—are all heated until just beginning to melt. For each compound, the cation and anion charges and approximate ionic radii are given in the table below.| Compound | Cation charge | Anion charge | r₊ (pm) | r₋ (pm) |
|---|---|---|---|---|
| LiF | +1 | –1 | 76 | 133 |
| KBr | +1 | –1 | 152 | 196 |
| CaO | +2 | –2 | 100 | 140 |
| Al₂O₃ | +3 | –2 | 67 | 140 |