Answer:
D
Explanation:
This question is a little strange. C and D are very similar, but I would pick D.
Fluorine actually has the highest electronegativity of all the elements. This allows it to pull more electrons towards itself. Since electrons have a negative charge, this causes the fluorine end of the molecule to be more negative while the hydrogen is left striped of electrons and has it positively charged necleus exposed. This means that one end of the molecule is positive while the other is negative, which makes this molecule polar. The only reason I would pick D over C is that D addresses the second part of the question about the covalent bond. A covalent bond is simply when two atoms share electrons.
Let me know if this was right and I hope it helps.
Explanation:
Let us assume that the value of =
Also at 1500 K, =
Relation between and is as follows.
Putting the given values into the above formula as follows.
Also,
or,
=
=
Thus, we can conclude that the value of is .
Answer:
Copper turns green on exposure to air
Explanation:
Liquid water freezes to form ice: Physical change
Reason: Water can melt back when it becomes ice.
Copper turns green on exposure to air: Chemical change
Reason: The copper can not change back from the green state when it turns green.
Answer:
ΔU = - 168 KJ
Explanation:
- ΔU = Q + W.....................first law
∴ W = - 61 KJ........A system performs on its surroundings
∴ Q = - 107 KJ,,,,,,A system release heat
⇒ ΔU = - 107 KJ - 61 KJ = - 168 KJ