If I had a 10lb solid block of dry ice stored in deep freeze and I took it out and placed it in a room at normal room temperature, how long would it take to melt?
Also, is it possible to freeze things inside a block of dry ice as it is with normal ice (think David Blaine & his iceman trick)?
I’ll admit this is nitpicking, but…
At room temperature & atmospheric pressure, dry ice doesn’t melt; it sublimates (changes from solid directly to a gas without going through a liquid phase).
Nitpick: Dry ice doesn’t “melt,” it sublimes. It turns directly from solid to gas, which isn’t really considered melting. Dry ice evaporates rather than melts.
I have a dry-ice sublimation calculating slide rule that I got from my grandfather, it was used in the olden days when rail cars were packed with dry ice to keep them cool. I’ll go dig it up and see what I can figure out about your query.
A ~2X10X10" block will take several hours to sublimate at room temp. If it’s humid out the block will pull moisture from the air and give itself a bit of insulation.