For a pressure of 1.00 atm and a temperature of 24.0 ∘C, use the ideal-gas law to estimate the number of air molecules in the room. Assume all the air is N2. Express your answer to three significant figures and include the appropriate units

mass of air = 324 kg

Explanation:

mass of air = moles of air × molecular weight (N₂)

moles of air = PV / RT

Given that

P = 1 atm

Volume of room = 282 m³

R = 0.082L atm mol⁻¹k⁻¹

                   = (1 × 282 × 10³) / (0.0821 × 297)

                   = 11.565 × 10³mol

molecular weight of N₂ = 28g/mol

mass of air = (11.565 × 10³)mol × 0.028kg/mol

                  = 323.8kg

to three significant figures = 324 kg

- 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

a 20-cm-long, cylindrical graphite (pure carbon) rod is inserted into an oxidizing atmosphere at 1145 k and 1.013 x 105 pa pressure. the oxidizing process is limited by the diffu- sion of oxygen counterflow to the carbon monoxide that is formed on the cylindrical surface.