Answer:
The statement that best describes the trend in first ionization enery of elements on the periodic table is:
It generally decreases down a group because valence electrons are farther from the nucleus.
The first ionization energy measures how difficult is to release an electron from the outermost shell. The higher the ionization energy the more difficult it is to release an electron, the lower the ionication energy the easier to release an electron.
As the atomic number of the atom increases (which is what happens when you go down a group) the furthest the outermost shell of electrons will be (the size of the atoms increases) and so those electrons require less energy to be released, which means that the ionization energy decreases.
Hope it helps!
<span>To find the volume of the plate without accounting for the hole firstly
V = (15.0 cm)(12.5 cm)(0.250 cm) = 46.875 cm^3
and the volume of the hole is
(pi)(1.25 cm)^2(0.250 cm) = 1.2272 cm^3
we will subtract the volume of the hole from the rest 45.648 cm^3
the multiply this by the density of the alloy to find the mass
(8.80 g/cm^3)(45.648 cm^3) = 401.701 g.
0.044% of this is Si, so (0.00044)(401.701 g) = 0.17675 g is silicon.
by the number of atoms and using average atomic mass of silicon and Avogadro's number to find the number of silicon atoms:
(0.17675 g)(1 mol/28.0855 g)(6.022E23 atoms/1 mol) =3.794E21atoms of Si
3.10% of these are Si-30:(0.0310)(3.794E18 atoms)=1.176E20 atoms of Si-30 and with two significant figures, 1.2E20 atoms.
hope this helps
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Answer:
the raising atomic number
Explanation:
Elements are listed on the periodic table according to their atomic number.
Answer:
<u> </u>H2 + <u>2</u><u> </u> Cl2 = <u>2</u><u> </u> HCl2