Answer:
C. naturally uncombined with other elements.
Explanation: Calcium is a chemical element with the symbol Ca and atomic number 20. As an alkaline earth metal, calcium is a reactive metal that forms a dark oxide-nitride layer when exposed to air.
Answer:
There are 3600 pages to 2 significant figures
Explanation:
Working only with the information given, we have that there are 23 books each with about 31 chapters.
This means that if 1 book has 31 chapter, the 23 science books will have
31 X 23 chapters =713 chapters in total.
If each chapter contains 5 pages, for the 713 chapters we will have a total of 713 X 5 pages = 3565 pages.
Rounding off the answer to 2 significant figures , we are looking to have only two non-zero figures in our answer. To do this, we count two numbers from the left. This will be numbers 3 and 5.
Next, we check the net number after 5 to see if it is greater than 5 if it is, we will have to add the number (1 ) to the 5. This shows that we are approximating upwards, to account for the fact that that number has passed the middle point.
After this, we change the remaining two numbers (6 and 5) to zeroes.
This will give us 3600 pages.
Answer:
Here's what I get.
Explanation:
The MO diagrams of KrBr, XeCl, and XeBr are shown below.
They are similar, except for the numbering of the valence shell orbitals.
Also, I have drawn the s and p orbitals at the same energy levels for both atoms in the compounds. That is obviously not the case.
However, the MO diagrams are approximately correct.
The ground state electron configuration of KrF is

KrF⁺ will have one less electron than KrF.
You remove the antibonding electron from the highest energy orbital, so the bond order increases.
The KrF bond will be stronger.
Answer:
this answer is hard cant answer