With an atomic number of 55, that means there are 55 protons. Because electrons do not count towards atomic weight, the element would have 150-55 neutrons. So, 95 neutrons.
Answer:
A barium atom would be expected to contain 2 electrons in its outer energy level.
Explanation:
The columns of the periodic table are called groups. There are eighteen groups, numbered from 1 to 18.
The elements of each group have the same number of electrons in their last atomic shell, which is why they have similar chemical properties, because the chemical properties of chemical elements are strongly related to the electrons located in the last atomic shell.
That is, in a group, the chemical properties are very similar, because all the elements of the group have the same number of electrons in their last or last shells.
<u><em>A barium atom would be expected to contain 2 electrons in its outer energy level.</em></u>
A.how many moles of aspirin are in one tablet
0.325 g ( 1 mol / 180.2 g ) = 1.80 x 10^-3 mol
B. How many moles of oxygen are in one tablet of aspirin
1.80 x 10^-3 mol C9H8O4 ( 4 mol O / 1 mol <span>C9H8O4) = 7.21 x 10^-3 mol O
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C. How many atoms of carbon are in one tablet of aspirin
1.80 x 10^-3 mol C9H8O4 ( 9 mol C / 1 mol C9H8O4 ) ( 6.022 x 10^23 atoms C / 1 mol C ) = 9.76 x 10^21 atoms C
D. How many grams of oxygen in one tablet of aspirin
7.21 x 10^-3 mol O ( 16 g / mol ) = 0.12 g O
Sodium metal and water form aqueous sodium hydroxide and hydrogen gas:
Na(s) + 2H2O(l) → (Na+)(aq) + 2(OH-)(aq) + H2(g)
Looks like your entries didn't translate well on screen, so find the solution with the coefficients and ions which match this one.