The phrase "it becomes unclear" is correct and usable in written English.
You can use it when discussing a situation or statement that lacks clarity or is difficult to understand.
Example: "As the discussion progressed, it becomes unclear what the main objective of the meeting was."
Alternatives: "it is not clear" or "it becomes ambiguous."
If we do not understand the particular role of a receptor in the normal physiology of an organism, that is, the consequences of its activation or inhibition, it becomes unclear whether effects seen following exposure to a particular pharmaceutical are due to specific effects caused at a particular target, a side-effect, or indeed a toxic effect.
Of fundamental interest is the rate of surface etching but when this involves multicomponent surface reactions, it becomes unclear how the overall rate can be estimated.
In extreme cases, such as Fox's troubled Fantastic Four, the intervention is so aggressive that it becomes unclear what it means to be the director.
In addition, at a time when other convening powers, like the G20, are deeply engaged in similar topics, it becomes unclear where the primary or optimal fora really lie.
On the one hand, Indianness starts to seem nebulous: it becomes unclear what it means for a person to identify him or herself as Indian or as an Indian artist.
The celebrity seems to have all the power, but soon it becomes unclear who is the more obsessed: the fan, or the comedian who craves the approval of his public.
As soon as the international organisation ceased its financial support, it became unclear for the health actors who should continue these activities, the hospital or the district authorities".
Still, as the service started to grow, it became unclear whether Dorsey had the wherewithal to manage it.
It became unclear toward the end of the cross-examination who, if anyone, was benefiting from Mr. Godineaux's testimony, the defense or the prosecution.
(At one point, a friend of Beatriz's popped in for a minute and the teen-agers swapped phones and it became unclear who was texting whom about what). Then it was time to take photographs to feed into the facial-recognition software.
So many different versions of "the TechCrunch green" were in play that it became unclear even to us what the official green of record was.
