Name some compounds and please amswer me guys Im from Australia and please follow broLusss

Some common compounds in our daily lives:

Water, H2O. We need this for survival, because it serves a lot of functions in our body, such as being a medium for chemical reactions in our cells.

Carbon Dioxide, CO2. It is one of the components of air, our body also produces CO2 during respiration.

Sodium chloride, NaCl. Table salt is mostly made of sodium chloride. It is also found dissolved in sea water.

Methane, C2H4. This is a common fuel for generating electricity. It can also be found (small amounts) in air.

Nitrogen Dioxide, NO2. It can also be found in air, and it is one of the common air pollutants brought by burning of fossil fuels.

- 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