Indicate the direction of polarity of each of the following covalent bonds by dragging the appropriate delta notation to each end of the bond.
just write a + or - not the bonds.
c-o
o-cl
o-f
c-n
cl-c
s-h
s-cl

The delta notation that indicates the direction of polarity for each of the given covalent bonds are:

δ+ C-O δ-

δ- O-Cl δ+

δ+ O-F δ-

δ+ C-N δ-

δ+ C-Cl δ-

δ- S-H δ+

δ+ S-Cl δ-

Polar bonds are those in which the atoms of their elements have a difference in electronegativities.

Now, the more electronegative atom is the one that can attract pair of bonded electrons to itself and as a result will possess a partial negative charge. In contrast, the less electronegative atom will possess a partial positive charge.

Finally, the direction of polarity of covalent bonds will flow from the less electronegative atom to the atom that is more electronegative.

Let us state the electronegativities of all the elements stated in this question;

1) Electronegativity of Carbon; C = 2.5

2) Electronegativity of Oxygen; O = 3.5

3) Electronegativity of Chlorine; Cl = 3

4) Electronegativity of Fluorine; F = 4

5) Electronegativity of Nitrogen; N = 3

6) Electronegativity of Sulphur; S = 2.5

7) Electronegativity of Hydrogen; H = 2.1

Thus;

1) C-O; O is more electronegative than C an as such will have the charge δ- while C will have δ+.

2) O-Cl; O is more electronegative than Cl an as such will have the charge δ- while Cl will have δ+.

3) O-F; F is more electronegative than O an as such will have the charge δ- while O will have δ+.

4) C-N; N is more electronegative than C an as such will have the charge δ- while C will have δ+.

5) Cl-C; Cl is more electronegative than C an as such will have the charge δ- while C will have δ+.

6) S-H; S is more electronegative than H an as such will have the charge δ- while H will have δ+.

7) S-Cl; Cl is more electronegative than S an as such will have the charge δ- while S will have δ+.

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The bond is said to be polar if there is difference in electronegativity between atoms of elements. Here, the more electronegative atom can attract bonding pair of electrons towards itself and gets partial negative charge. Partial positive charge is acquire by atom of less electronegative element. The direction of polarity will be from less electronegative to more electronegative atom.

C-O:

Here, oxygen(3.44) is more electronegative than carbon(2.55) thus, it can be represented as:

O-Cl

Here, oxygen(3.44) is more electronegtive than chlorine(3.16) thus, it can be represneted as:

0-F

Here, fluorine(3.98) is more electronegative than oxygen(3.44) thus, it can be represented as:

C-N

Here, nitrogen(3.04) is more electronegative than carbon(2.55) thus, it can be represented as:

Cl-C

Here, chlorine(3.16) is more electronegative than carbon(2.55) thus, it can be represented as:

S-H

Here, sulfur(2.58) is more electronegative than hydrogen(2.20) thus, it can be represented as:

S-Cl

Here, chlorine(3.16) is more electronegative than sulfur(2.58) thus, it can be represented as:

- calcium has greater affinity to bond with electron receptors than hydrogen does and hence, it has the ability to replace hydrogen in most of its compounds.

- lithium has 2 valence electrons in the product because it can make only 1 bond with hydrogen. beryllium has 4 valence electrons in the product because it can only make 2 bonds. it has fewer electrons than neon and can react with electron donors. each hydrogen has 2 valence electrons, the same as helium.

- the covalent bond formed between carbon and hydrogen is polar because carbon is more electronegative than hydrogen and it attracts the bonded electron pair closer to itself, thus giving hydrogen a partial positive charge.

- a hydrogen bond is a relatively weak bond that hydrogen atoms make with the electronegative atoms nitrogen, oxygen or fluorine.

so the best choice is a.) 2 calcium (ca) atoms