They have less or more neutrons. Isotopes have same number of protons but different number of neutrons.
The water cycle? hope this helped
The Fe charge is 2+ and the O charge is 2- so the ratio is 1:1
FeO
Infrared (IR) spectroscopy uses infrared radiation to excite the molecules of a compound and generates an infrared spectrum of the energy absorbed by a molecule as a function of the frequency or wavelength of light
To answer this question, all you to do is to divide the mass by the molar mass and that should get you your moles.

<em>= 3.5 mol NH₄</em>
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