Question

in ming china why did european traders pay for chinese silks and porcelains in gold or silver instead of extanging trade gods

Answer 1

Assuming that you made typos, and it's supposed to say "exchanging trade goods."

In order to exchange trade goods with a partner, you have to have something that that partner wants. The European traders had nothing that the Chinese wanted. Therefore, they had to pay for their silk and porcelain in gold and silver.