Visual representation of covalent bonding indicating the valence shell electrons in the molecule, lines represents the shared pair of electron and pair of electrons that are not involved in bonding are represented as dots(lone pairs) are known as Lewis structures.
Compound formation takes place in order to complete the octet of each element that is according to octet rule, each atom forms bond with other atom in order to complete their octet that is to get eight electrons in its valence shell and attain stability.
An organic compound of the form 
is known as ketene.
The given ketene is 
.
The number of valence electron of:
The number of valence electrons in = 
2 electrons are involved in each single bond between carbon and hydrogen and 4 electrons are involved in each double bond formed between carbon-carbon and carbon-oxygen. Hence, the total number of electrons involved in bond formation are 12 and rest 2 pair of electrons are present on oxygen as lone pair of electrons.
Therefore, the attached image is the Lewis structure of .
Answer:
The correct options are:
1) Pure chemical substance
2) Element.
Explanation:
each of the term is explained below:
1) <u>Mixture: </u> Since tungsten is an element in periodic table thus it is not a mixture.
2) False by definition of mixture.
3) false by definition of mixture.
4) <u>Solution:</u> Tungsten in a filament is in solid form hence solution is incorrect.
5) Since it is given in the question itself that the sample is pure hence option 'E' is correct as chemical substance is a pure substance that has a homogeneous composition and the sample in the question is given as pure.
6) <u>Compound:</u> By definition of compound it is formed by mixing 2 or more elements but since tungsten is an element that occurs independently in nature hence it is not a compound.
7) Tungsten is a element in the periodic table with atomic number 74.
The concentrations of a mixture at equilibrium are constant as a function of time because the <span>e forward reaction proceeds at the same rate as the reverse reaction.</span>
