When a gas bubbles through water, small droplets of water are usually picked up along for the ride and are mixed in with the gas above the water inside the eudiometer tube. The water vapor takes up room, but isn't the important gas that you need to measure. The table of water vapor is needed to subtract the unwanted water vapor from the collection of gases.
To calculate the average mass of the element, we take the summation of the product of the isotope and the percent abundance. In this case, the equation becomes 186.207=187*0.626+185*x where x is the percent abundance of 185. The answer is 0.374 or 37.4%. This can also be obtained by 100%-62.6%= 37.4%.
Answer:
28
Explanation:
28 is correct. (NH4)2 is equal to 10 atoms. (8 H and 2 N ) CO3 is equal to 4 atoms. (1 C and 3 O) That's 14 atoms. But it's two molecules of this. So you just multiply by the number of molecules (2), and you get 28.
Most of the mass of an atom comes from the electron cloud would NOT describe the structure of an atom