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Serhud [2]
4 years ago
7

Which Of These Elements Has Four Valence Electrons? Hafnium Radon Silicon Sulfur

Chemistry
2 answers:
Free_Kalibri [48]4 years ago
8 0
Silicon has 4 valence Electron may be
zvonat [6]4 years ago
4 0

Answer : The elements that has four valence electrons are hafnium (Hf) and silicon (Si).

Explanation :

Electronic configuration : It is defined as the representation of electrons around the nucleus of an atom.  

Number of electrons in an atom are determined by the electronic configuration.

Atomic number : It is defined as the number of electrons or number of protons present in a neutral atom.

Valence electrons or outermost electrons : They are electrons in an atom that participate in bonding.

(a) Hafnium is a metal that belongs to group 4 and period 6. The atomic number of Hafnium is, 72.

The electronic configuration of hafnium will be,

[Xe]4f^{14}5d^26s^2

The total number of valance electrons = [2 + 2] = 4

(b) Radon is a noble gas that belongs to group 18 and period 6. The atomic number of radon is, 86.

The electronic configuration of radon will be,

[Xe]4f^{14}5d^{10}6s^26p^6

The total number of valance electrons = [2 + 6] = 8

(c) Silicon is a non-metal that belongs to group 14 and period 3. The atomic number of silicon is, 14.

The electronic configuration of silicon will be,

1s^22s^22p^63s^23p^2

The total number of valance electrons = [2 + 2] = 4

(d) Sulfur is a non-metal that belongs to group 16 and period 3. The atomic number of sulfur is, 16.

The electronic configuration of sulfur will be,

1s^22s^22p^63s^23p^4

The total number of valance electrons = [2 + 4] = 6

Hence, from this we conclude that, the elements that has four valence electrons are hafnium (Hf) and silicon (Si).

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A chemist measures the energy change ΔH during the following reaction: C3H8 (g) +5O2 (g) →3CO2 (g) +4H2O (l) =ΔH−2220.kJ Use the
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Yes, released.

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<em>-Using molar mass of C₃H₈ to convert mass to moles and knowing that there are released 2220 kJ per mole of C₃H₈-</em>

I hope it helps!

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