all the elements in group 18 are Nobel gases or inert gases . all the elements such as neon , helium, argon etc. ,their outermost shell is completely filled . The noble gases have the largest ionization energies, reflecting their chemical inertness
They have the same density because a material, no matter how much of it there is, will always be a certain density. A 40g ball of iron has the same density as a 1g ball of iron.
8798076 atoms are in a 0.3500 mol of gold
Because atoms are the small and can't be seen by your eyes. It is so small that scientists need to use a model. A model help scientists study things. So, scientists needs to study atoms using models.
Answer: 106.905
Explanation: If there are only 2 isotopes, and 1 of them is 48.16%, the second must, by default, be (100 - 48.16%) = 51.84% The final, averaged, atomic mass is 107.868. This is made up of each isotope's atomic mass times the percentage of that isotope in the total sample. The weighted value of the known isotope (109) plus that of the unknown must come to the observed value of 107.868 amu. (107.868 - 52.45 = 55.42). Divide that by the % for that isotope (55.42/0.5184) = 106.90 amu for the second isotope.
<u>Atomic Mass</u> <u>% of Sample</u> <u>Weighted Value</u>
108.905 48.16% 52.45
X 51.84% <u>55.42</u>
107.87
X = (55.42/0.5184) = 106.90 amu
