Inspired by this question, I thought of two ways to talk about checking the truth of something, though I think my question applies much more generally than with just the verb 'to check'.
雪が溶けていることを確認した。
雪が溶けているか(を)確認した。
I checked to see if the snow had melted.
My suspicion is that in the first sentence I am making the assumption that the snow has melted and I am simply verifying my assumption. Whereas, in the second sentence, I have no initial theory on what the result will be.
Are my sentences both valid? Is my theory correct? What did I get wrong?
