Which of the following is true regarding the inner transition elements? (pf)

a. these include the lanthanides and actinides and do not have f sublevels.
b. they occupy the d block of the periodic table.
c. these include all elements in groups 3-12.
d. their valence electrons can be located in both s and f sublevels.

The answer is D

Explanation:

The inner transition elements are those in the two long rows at the bottom of the Periodic Table.

The lanthanide series starts after Ba in Period 6, and the actinide series starts after Ra in Period 7.

Thus, we would predict their electron configurations to be of the form

However, the energy levels of the ns, (n-1)d, and (n-2)f orbitals are so close in energy that there are many exceptions to our predictions

For example, here are some electron configurations.

La = [Xe]6s²5d (not [Xe]6s²4f)

Ce = [Xe]6s²4f5d (not [Xe]6s²4f²)

Pr = [Xe]6s²4f³ (as predicted)

Thus, their valence electrons can be in both s and f (and sometimes d) sublevels.

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- 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

im pretty sure its b