3 - b) weight decreases
4 -a) 50 kg as mass is same everywhere
5 - b) 200 dynes
During a single replacement, the Zn and H will switch places. That means the product formed will be ZnCl and H2.
The pyrite will be bigger, because its density is much lower.
I <em>do</em> know that the gold's volume will be 2.5906 (With a bunch more numbers after it)
50 divided by 19.3 = 2.5906
It’s c.) I think so at least
