Answer:
All are correct
Explanation:
This might be a little deceptive. The question shows H, O and N which would designate ELEMENTS.
However, all of these can also be considered compounds and molecules as well. BUT, they are H₂, O₂ and N₂ when they are molecules and compounds.
So it depends on the whether the question is being literal or not.
reference refers to something that is not moving with respect to an observer that can be used to detect motion. But if they use objects outside the bus as their frame of reference, they can tell they are moving.
:)
17) 8.4 / 20 x 100
18) 20 . 0.5150
19) 6,50% because (as you said) the law of definite proportions states that regardless of the amount, a compound is always composed of the same elements in the same proportion by mass
Answer:
0.305 mol
Explanation:
Ca(NO) is not a molecule. I think you meant to type Ca(NO3)2, which is calcium nitrate.
The moles of a compound is equal to is mass divided by its molar mass.
The molar mass of Ca(NO3)2 is 164.09 g/mol.
50.0 / 164.09 = 0.305