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3 years ago

Hafnium: atomic number

Chemistry

1 answer:

telo118 [61]3 years ago

8 0

The question is incomplete. The complete question is as follows:

Use the periodic table to identify the name or atomic number for each element below. (Give the name, not the chemical symbol, for each element.)

hafnium: atomic number

atomic number 15

atomic number 45

osmium: atomic number

magnesium: atomic number

Answer:

hafnium: atomic number - 72

atomic number 15 - Phosphorus

atomic number 45 - Rhodium

osmium: atomic number - 76

magnesium: atomic number - 12

Explanation:

A Periodic table is a tabular representation of elements or atoms arranged on the basis of their atomic number and atomic mass.

So according to the periodic table:

Hafnium is metal and atomic number of hafnium is 72 that lies in group 4 (IVb) of the periodic table.
Atomic number 15 in the periodic table represents Phosphorus with the symbol P.
Atomic number 45 in the periodic table represents Rhodium with symbol Rh.
Atomic number of osmium is 76 that lies in Group 8 (VIIIB) of the periodic table.
Atomic number of magnesium is 12 that lies in group 2 (II) of the periodic table.

Hence, the correct answer is:

hafnium: atomic number - 72

atomic number 15 - Phosphorus

atomic number 45 - Rhodium

osmium: atomic number - 76

magnesium: atomic number - 12

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Answer:

The answer is

<h2>12,574,750.83 moles</h2>

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From the question

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We have

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