12gHe/1 × 1molHe/4.0026g × 6.02x10^23atomHe/1mol = 1.8 atoms
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<span>moles HClO4 = 0.100 L x 0.18 M = 0.018
moles LiOH = 0.030 L x 0.27 = 0.0081
moles H+ in excess = 0.018 - 0.0081 = 0.0099
total volume = 0.130 L
[H+] = 0.0099/ 0.130= 0.0762 M
pH = 1.12</span>
There are various kind of elements that are present in periodic table. Some elements are harmful, some are radioactive, some are noble gases. The atomic radius in decreasing order is Bi>Sb>As>N>O.
<h3>
What is periodic table?</h3>
Periodic table is a table in which we find elements with properties like metals, non metals, metalloids and radioactive element arranges in increasing atomic number.
Along the period, the size of elements decreases. Down the group the size of elements increases. The atomic radius in decreasing order is Bi>Sb>As>N>O.
Therefore, atomic radius in decreasing order is Bi>Sb>As>N>O.
Learn more about periodic table, here:
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Fluorine needs one electron to fill its orbital shell. It needs 8 valence electrons