Let’s split this meat bun between two people.
It was a decision that spelt the difference between life and death.
If you split the pizza, could you give me the bigger half?
This word consists of kanji with hiragana attached. Because the hiragana ends with an う (in this case る) sound, you know this word is a verb. The kanji itself means separate (at least, that's one of its several meanings). So, the verb form of that is to separate, to divide, to share or to split.
You'll have to differentiate this word with 分かる which is very similar but has a totally different meaning. You'll need to learn the reading to do this, but think of it this way: You must "separate" your Wake (わけ) time from your sleeping time.
Since this word consists of a kanji with hiragana attached, you can bet that it will use the kun'yomi reading. You didn't learn that reading with this kanji, so here's a mnemonic to help you:
You are to separate a couple of children that really have fun together. When you separate them, they begin to cry and scream: WAAAAAAAAAHHHH (わ). Poor kids.