Chromium (Cr) is round in d block
Answer:
The law of conservation of mass states that matter can not be created or destroyed in a chemical reaction.
Explanation:
I would say C. Permable
Google def.(of a material or membrane) allowing liquids or gases to pass through it.
"a frog's skin is permeable to water
Porous- (of a rock or other material) having minute spaces or holes through which liquid or air may pass
Answer : The correct option is, 13.7 mole
Solution : Given,
Moles of 
= 27.4 moles
The given balanced chemical reaction is,
From the balanced chemical reaction, we conclude that
As, 2 moles of react with 1 moles of 
So, 27.4 moles of react with 
moles of
Therefore, the number of moles of oxygen required are, 13.7 moles
