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please help GCSE chemistry

ammonia reacts with oxygen in the presence of a metal oxide catalyst to produce nitrogen and water.
which metal oxide is most likely to be a catalyst for this reaction?
a) CaO
b) Cr2O3
c)MgO
d)Na2O
the answer is b but I don't understand why

Reply 1

have a think about the metals involved in the compounds
what type of elements are often used as catalysts?

Reply 2

Original post by bl0bf1sh
have a think about the metals involved in the compounds
what type of elements are often used as catalysts?


never mind i get why now thanks :smile:

Reply 3

please could you explain why

Reply 4

Original post by crochetnbooks
please could you explain why

Look at the groups the metals are in. That should give you the answer.

Reply 5

transition metals act as catalysts

Reply 6

Original post by butter fly
never mind i get why now thanks :smile:

Could you please tell me why too?

Reply 7

Original post by Elliezhou
Could you please tell me why too?

Transition metals, and transition metal compounds, are often good catalysts.

chemguide has a nice page about transition metals scroll down a bit and there's a section on catalytic activity:
https://www.chemguide.co.uk/inorganic/transition/features.html

And on catalysts in general:
https://www.chemguide.co.uk/physical/catalysismenu.html
https://www.chemguide.co.uk/physical/catalysis/introduction.html
You'll see that many of the examples of catalysts used are transition metals :smile:

Spoiler

Reply 8

Original post by bl0bf1sh
have a think about the metals involved in the compounds
what type of elements are often used as catalysts?

is it because cr is a transition metal?

Reply 9

Original post by bl0bf1sh
have a think about the metals involved in the compounds
what type of elements are often used as catalysts?

nvm i saw ur later message lol ty

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