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Reika [66]
3 years ago
10

HELP ASAPPPP

Chemistry
1 answer:
Cloud [144]3 years ago
3 0

Answer:

13 years

Explanation:

From;

0.693/t1/2 = 2.303/t log (No/N)

Where;

t1/12 = half-life of Cobalt-60 = 5.3 years

t = time taken = the unknown

No = mass of radioactive material originally present = 5.2 g

N = mass of radioactive material at time t = 0.95 g

Substituting values;

0.693/5.3 = 2.303/t log (5.2/0.95)

0.131 = 2.303/t(0.738)

0.131 = 1.6996/t

t =  1.6996/0.131

t = 12.97 years

t = 13 years(to the nearest whole number)

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Answer:

See explaination

Explanation:

1)

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lower the reduction potential , stronger the reducing agent

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reducing agents

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The answer is- SF_{6} is octahedral in electronic and molecular geometry with 6 Fluorine atoms bonded to central atom S.

Lewis structures are the diagrams in which the valence electrons of the atoms of a compound are arranged around the atoms showing the bonding between the atom and the lone pair of electrons existing in the molecule.

Determine the molecular geometry of SF_{6}.

  • Valence Shell Electron Pair Repulsion theory is commonly known as VSEPR theory and it helps to predict the geometry of molecules.
  • According to this theory, electrons are arranged around the central atom of the molecule in such a way that there is minimum electrostatic repulsion between these electrons.
  • Now, calculate the total number of valence electrons in SF_{6}.

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  • Molecular geometry us also octahedral with bond angles 90°.
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  • SF_{6} is a non-polar molecule.

To learn more about Lewis structures visit:

brainly.com/question/12307841?referrer=searchResults

#SPJ4

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