How many moles of calcium are there in 5.74 x 1022 atoms of calcium?

0.095 moles of Calcium is there in 5.74 x 1022 atoms of calcium.

Explanation:

       And, 6.023*10^23 atoms of an element is also equal to 1 mole of the             element.

We have,

         (1/(6.023*10^.23)) * 5.74*10^22 moles of calcium

Therefore,

- 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