Question

I just took a test and I missed four questions. I need help on the ones I missed.
~Based on electronegativity differences, between which two elements will a bond result in a highly unequal sharing of electrons?
A. Chlorine and lithium
B. Aluminum and chlorine
C. Lead and sulfur
D. Nitrogen and oxygen
~All the following are signs of a chemical reaction, except
A. a change in energy.
B. a change of state.
C. a release of gas.
D. a change in color or odor.
~Which of the following is the least reactive nonmetal?
A. Br
B. F
C. I
D. Cl

Answer 1

Which of the following is true regarding the inner transition elements?

A. These include all elements in groups 3–12.
B. Their valence electrons can be located in both s and f sublevels.
C. These include the lanthanides and actinides and do not have f sublevels.
D. They occupy the d block of the periodic table.

This was the last question I couldn't fit

Answer 2

OK. Most of your answers can be found looking at the periodic table. You can either jot down the electronegativity values for each element and calculate the difference or find what group they're in and compare what type of bonds they form.
You have:
Li
Cl
Al
Pb
S
N
O

Now, to know which of the options you have will result in a highly unequal sharing of electrons you'll have to do the math.
The strength of the bond is given by how much each atom is 'pulling' the electrons towards them. So you have to find the two E values you need in your periodic table.
For example:
The electronegativity of Lithium is 1
And the electronegativity of Chlorine is 3. Either 3 minus 1 or 1 minus 3 gives us a value of two. I think of it as how much the Chlorine wants the electrons for itself.
If the bond is equal or bigger than two you have a ionic bond. If the value is less than that you have a covalent bond. Of course this isn't always the case, because there are some bonds in the middle that could have ionic character or covalent character.
The point is, if it is ionic one is giving an electron, the other receiving it. If it is covalent they're sharing it.
What happens in your case?. Which species is 'pulling' from the electrons harder?
I hope this works for you.

Answer 3

In the second, if it's not a chemical reaction then it is a physical change, right?
The third is almost the same as the first one, which one is the most reactive, or say more electronegative?
The last one is harder to see. The block d on the periodic table belongs to transition metals, but the question asks specifically for Inner transition metals, those are indeed the ones that belong to lanthanides and actinides. They're not all of the elements of the block d.

Answer 4

Thank you so much! I really appreciate you taking the time to explain that to me. It helped greatly.

Answer 5

No problem, I can always count on someone in this forum. It's great it helped

Answer 6

Don't forget to close this question if you've gotten help already (: