The mass of 1 mole of an element is its atomic weight on the Periodic Table in grams.
1g = 1000mg
The mass of 1 mole of Kr = 83.80g Kr
Convert mg Kr to g Kr.
398mg Kr x (1g/1000mg) = 0.398g Kr
Convert g Kr to mol Kr.
0.398g Kr x (1mol Kr/83.80g Kr) = 4.75x10-3mol Kr
Answer:
All you have to do is count the number of electrons in the shells and place them according to the atomic number. I just did it.
Explanation:
C. Because skin acts like a barrier that doesn’t allow pathogens or other micro organisms to enter unless their is a cut, scratch, etc. on your skin.
Color implies visible light, so to answer your question: red light has the longest wavelength (~620 - 740 nm). However, there also exists light with even longer wavelengths that is not visible to the human eye, from infrared light to radio waves (with wavelengths that are meters long!)
