Q.State true or false. Correct the false statement.
The acidic nature of oxides of group 13 increases down the graph.

Step 1. Check against Table 9.6. Table 9.6 lists, for group 13: B2O3 acidic, Al2O3 amphoteric, Ga2O3 amphoteric, In2O3 basic, Tl2O3 basic — moving down the group from acidic to amphoteric to basic.

Step 2. State the correction. So the statement as printed ('acidic nature... increases down the group') is the reverse of what the table shows — acidic character decreases (basic character increases) down the group, tracking the increase in metallic character down the group (section 9.4.3). …

Checking the statement directly against Table 9.6's acidic/amphoteric/basic c …

• Marking this True by only remembering that SOME group-13 oxides are acidic, without checking the a …