They are odourless, colourless monatomic gases with full outer shells
Answer:
all of above
<h3>please please mark me as a brainliest</h3>
Answer:
they produce no DIRECT emissions
Explanation:
that is why they are good in cities to reduce air pollution . but sometypes can produce lesser emissions.
<span>Catalysts decrease the activation energy and the more collisions result in a </span>reaction<span>, so the </span>rate<span> of </span><span>reaction increases.</span><span />
