Determine the number of atoms of O in 58.3 moles of Na₂Cr₂O₇.

2457.58×10²³ atoms of oxygen

Explanation:

Given data:

Number of moles of Na₂Cr₂O₇ = 58.3 mol

Number of atoms of oxygen = ?

Solution:

First of all we will calculate the number of moles of oxygen in 58.3 moles of Na₂Cr₂O₇.

1 mole of Na₂Cr₂O₇ contain 7 moles of oxygen.

58.3 mol × 7 = 408.1 mol

Number of atoms of oxygen:

1 mole contain 6.022×10²³ atoms

408.1 mol × 6.022×10²³ atoms / 1 mol

2457.58×10²³ atoms

gas

explanation:

smoke is the matter of a gas

hydrocarbons are organic compounds that contain only hydrogens and carbons. they can be saturated (those which contain only carbon-carbon single bonds) or unsaturated (those which contain carbon-carbon double or triple bonds) in nature. hydrocarbons can undergo several reactions like substitution, elimination etc.  

on substituting one or more hydrogen atoms in hydrocarbon it results in the formation of haloalkane. as the halogen atoms are large compared to the carbon and hydrogen atoms, due to which the molecular weight increases and the bond become polar because of presence electronegative halogen atom and results in the increase in boiling point of the haloalkane.

thus, the correct option is (b) that is the boiling point of the new compound increases on substituting a hydrogen atom with a halogen in a hydrocarbon.