an oil drum weights 11.8kg. when it is filled, octane it weighs 55.32kg. how many molecules of pentane c5h12 exist in this oil drum?

Question: an oil drum weights 11.8kg. when it is filled, pentane it weighs 55.32kg. how many molecules of pentane c5h12 exist in this oil drum?

3.64×10²⁶ molecules

Explanation:

Applying,

n = M/M.M Equation 1

Where n = number of moles of pentane, M = mass of pentane, M.M = reacting mass of pentane

From the question,

Given: M = 55.32-11.8 = 43.52 kg = 43520 g

Constant: M.M of octane (C₅H₁₂) = [(12×5)+(1×12)] = 60+12 = 72 g/mol

Substitute these values into equation 1

n = 43520/72

n = 604.44 moles

Therefore,

number of molecules = n×(6.02×10²³)

number of molecules = 604.44(6.02×10²³)

number of molecules = 3.64×10²⁶ molecules

- 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