Silver-plated utensils were popular before stainless steel became widely used to make eating utensils. Silver tarnishes when it comes in contact with hydrogen sulfide, H2S, which is found in the air and in some foods. However, stainless steel does not tarnish when it
comes in contact with hydrogen sulfide.

76 In the space in your answer booklet, draw a Lewis electron-dot diagram for the compound that tarnishes silver. [1]

77 In the ground state, an atom of which noble gas has the same electron configuration as the sulfide ion in Ag2S? [1]



Answer :

76 You would draw a covalent bond in which you have S in the middle, and 1 H either side of it. You then draw the outer shell electrons, ensuring that the other shell electron of H atoms is in the overlapping ring of the S atom, and that one outer shell electron from S is present in each of the overlaps with the H atoms.

For 77, the sulfide ion has gained 2 electrons, and so will have the same electron configuration as the noble gas at the end of its period - Argon

Answer:

Lewis electron-dot diagram for the compound that tarnishes silver is given in the image.

Argon is the noble gas that has the same electron configuration as the sulfide ion

Explanation:

Silver utensils become tarnish due to reaction of a silver with hydrogen sulfide to from a black color coating of silver sulfide.

[tex]2Ag+2H_2S\rightarrow 2Ag_2S+H_2[/tex]

Lewis dot structures are the structures in which atoms along with their valence electrons are shown, And electrons are represented by dots.

In the Lewis dot structure of hydrogen sulfide two hydrogen atom with 1 valence electron each surrounds sulfur atom which have 6 valence electrons.

.An atomic number of sulfur is 16.Electronic configuration of sulfur is:

[tex][S]=1s^22s^22p^63s^23p^4[/tex]

After gaining two electrons,sulfur atom becomes sulfide ions to gain stability of noble gas configuration.

[tex][S^{2-}]=1s^22s^22p^63s^23p^6[/tex]

Sulfur falls in third period in modern periodic period, in which the nearest noble gas to sulfur element is argon whose electronic configuration is given as:

[tex][Ar]=1s^22s^22p^63s^23p^6[/tex]

View image Tringa0