Answer:
1. Diagram C.
2. Diagram A.
Explanation:
1. Calcium atom, Ca has 20 protons and 20 electrons. On the other hand, Calcium ion, Ca^2+ has 20 protons and 18 electrons. This is true because the +2 charge on the calcium ion, Ca^2+ indicates that the calcium atom, Ca has loss 2 electrons.
From the above illustration we can say that calcium ion, Ca^2+ has the following:
Proton = 20
Electron = 18
Therefore, diagram C indicates calcium ion, Ca^2+.
2. Fluorine atom, F has 9 protons and 9 electrons. Fluoride ion, F¯ has 9 protons and 10 electrons. This is so because the –1 charge on the fluoride ion, F¯ indicates that the fluorine atom, F has gained 1 electron.
Thus, we can say that the fluoride ion, F¯ has the following:
Proton = 9
Electron = 10
Therefore, diagram A represent fluoride ion, F¯.
Answer:
b
Explanation:
beacuse when u reduce the concentration
To know this you pretty much do have to kind of memorize a few electronegativities. I don't recall ever getting a table of electronegativities on an exam.
From the structure, you have:
I remember the following electronegativities most because they are fairly patterned:
EN
H
=
2.1
EN
C
=
2.5
EN
N
=
3.0
EN
O
=
3.5
EN
F
=
4.0
EN
Cl
=
3.5
Notice how carbon through fluorine go in increments of
~
0.5
. I believe Pauling made it that way when he determined electronegativities in the '30s.
Δ
EN
C
−
Cl
=
1.0
Δ
EN
C
−
H
=
0.4
Δ
EN
C
−
C
=
0.0
Δ
EN
C
−
O
=
1.0
Δ
EN
O
−
H
=
1.4
So naturally, with the greatest electronegativity difference of
4.0
−
2.5
=
1.5
, the
C
−
F
bond is most polar, i.e. that bond's electron distribution is the most drawn towards the more electronegative compound as compared to the rest.
When the electron distribution is polarized and drawn towards a more electronegative atom, the less electronegative atom has to move inwards because its nucleus was previously favorably attracted to the electrons from the other atom.
That means generally, the greater the electronegativity difference between two atoms is, the shorter you can expect the bond to be, insofar as the electronegative atom is the same size as another comparable electronegative atom.
However, examining actual data, we would see that on average, in conditions without other bond polarizations occuring:
r
C
−
Cl
≈
177 pm
r
C
−
C
≈
154 pm
r
C
−
O
≈
143 pm
r
C
−
F
≈
135 pm
r
C
−
H
≈
109 pm
r
O
−
H
≈
96 pm
So it is not necessarily the least electronegativity difference that gives the longest bond.
Therefore, you cannot simply consider electronegativity. Examining the radii of the atoms, you should notice that chlorine is the biggest atom in the compound.
r
Cl
≈
79 pm
r
C
≈
70 pm
r
H
≈
53 pm
r
O
≈
60 pm
So assuming the answer is truly
C
−
C
, what would have to hold true is that:
The
C
−
F
bond polarization makes the carbon more electropositive (which is true).
The now more electropositive carbon wishes to attract bonding pairs from chlorine closer, thereby shortening the
C
−
Cl
bond, and potentially the
C
−
H
bond (which is probably true).
The shortening of the
C
−
Cl
bond is somehow enough to be shorter than the
C
−
C
bond (this is debatable).
Making lemonade is a chemical change because once the ingredients are mixed together they cannot be seperated.
Answer:
Throughout the description box below, the overview including its query is listed.
Explanation:
- Hypothesis: unless the food is colored, then it would be picked by the youngsters or kids.
- Independent Variable: The Hue Variable or color.
- Dependent variable: The proportion of children selecting the potatoes selected.
- Controlled variables: The community of plans.
- Control procedure or treatment: The color selection community.