[scientizscht (OP)]

How much precious metal is needed for automotive catalytic converters? (in average or any example would work)

What is the size of the precious metals particles that are put in catalytic converters and what is their number so that I can calculate the total mass in a brick?

Thanks

[scientizscht (OP)]

Still no reply, so disappointing

[Bored chemist]

What is the size of the precious metals particles that are put in catalytic converters and what is their number so that I can calculate the total mass in a brick?

It is easier to do that the other way round.

From
http://www.specialtymetals.com/faq/

"There are between 3-7 grams of platinum group metals in a standard catalytic converter, but the amount varies based on manufacturer and model. "

I can't find any data on the size of the metal  particles. But the only bit of the catalyst that can influence the gas phase is the surface so they make that as large as possible.
To do that they use very small particles.
I would guess at a micron or less in diameter.

It may take a while to count them.