A rule for (some) Chinese tones

I have just come across an interesting rule for the tones of some words on a Popup Chinese podcast. The rule was only mentioned in passing, perhaps because it only applies to a small number of words. The rule is for when a single character can represent a noun or a related verb, which have the same pronunciation, but a different tone:

The verb is third tone, while the noun is forth tone

It's perhaps wrong to call this a rule, since it only applies to a few words, and for all I know there may be counter-examples. However, I was surprised that there was any such regularity in the Chinese tones; the example given was a word with which I have often confused the tones:

处 chǔ - to reside, to live (also to get along with)
处 chù - place, bureau (also respect)

Also:

数 shǔ - to count, (also to criticize)
数 shù - number, figure, several

Since hearing this 'rule', I have only been able to think of one more possible example and I'm not sure you can really separate the words into noun and verb:

假 jiǎ - fake, to borrow, suppose
假 jià - vacation

Discovering that such a rule exists makes me wonder whether there are similar rules for other words that I often confuse. I looked for more characters with multiple tones and it seems that most have first and forth tones):

差 chā - difference, to differ, error, to err
差 chà - differ from, short of, to lack

发 fā - send out, develop
发 fà - hair

间 jiān - between
间 jiàn - gap, to separate

空 kōng - air, sky, empty, free time
空 kòng - emptied, leisure

要 yāo - demand, ask, coerce
要 yào - important, to want, going to (as future auxiliary), may, must

I've also come across this pair, which has a different tone combination (although the verb does have a third tone):

强 qiáng - strong, violent
强 qiǎng - to strive

I guess I will just have to learn the differences.