La cal (lime)
La capital (capital—town)
La cárcel (prison)
La col (cabbage)
La miel (honey)
La piel (skin)
La sal (salt)
La señal (signal)
La vocal (vowel)

And a few more.

9. Feminine nouns ending in n

La cargazón (the load)
La crin (the horsehair)
La desazón (the ailment)
La imagen (the image)
La razón (the reason)
La sinrazón (the injustice)
La sartén (the frying-pan)
La sien (the temple)

Almost all.

10. Feminine nouns ending in o

La mano (the hand)

Only word, excepting "nao" (ship), now obsolete, and "seo" (cathedral), little used.

11. Feminine nouns ending in r

La flor (the flower)
La labor (the needlework)
La segur (the axe)