Would it just be as effective or should I still try to take it dissolved in water?
If you search the forum for "
capsule" then you'll find threads (for background reading) but in short; you want the SN to be absorbed as fast as possible, which is why people fast/have an empty stomach, and dilute SN in water.
Taking a capsule would mean slow and uneven absorption, because you'd have to wait for the capsule to start dissolving, and at that point your stomach acid would've probably turned most of it into nitrate.