Arrange in increasing order bromoethane,bromomethane,bromopropane,bromobutane

To arrange the compounds bromoethane, bromomethane, bromopropane, and bromobutane in increasing order, we need to consider their molecular weights and the number of carbon atoms in each molecule. The general formula for these compounds is CnH(2n+1)Br, where 'n' represents the number of carbon atoms. Let's break this down step by step.

Understanding the Compounds

Here’s a quick overview of each compound:

• Bromomethane (CH3Br): This compound has one carbon atom (n=1).
• Bromoethane (C2H5Br): This has two carbon atoms (n=2).
• Bromopropane (C3H7Br): This contains three carbon atoms (n=3).
• Bromobutane (C4H9Br): This has four carbon atoms (n=4).

Calculating Molecular Weights

The molecular weights of these compounds can be calculated based on the atomic weights of carbon (C), hydrogen (H), and bromine (Br). Here are the approximate atomic weights:

• Carbon (C): 12.01 g/mol
• Hydrogen (H): 1.008 g/mol
• Bromine (Br): 79.90 g/mol

Calculating Each Compound's Weight

Now, let’s calculate the molecular weight for each compound:

• Bromomethane (CH3Br):
  • 1 C: 12.01 g/mol
  • 3 H: 3 x 1.008 g/mol = 3.024 g/mol
  • 1 Br: 79.90 g/mol
  • Total = 12.01 + 3.024 + 79.90 = 94.934 g/mol
• Bromoethane (C2H5Br):
  • 2 C: 2 x 12.01 g/mol = 24.02 g/mol
  • 5 H: 5 x 1.008 g/mol = 5.04 g/mol
  • 1 Br: 79.90 g/mol
  • Total = 24.02 + 5.04 + 79.90 = 108.95 g/mol
• Bromopropane (C3H7Br):
  • 3 C: 3 x 12.01 g/mol = 36.03 g/mol
  • 7 H: 7 x 1.008 g/mol = 7.056 g/mol
  • 1 Br: 79.90 g/mol
  • Total = 36.03 + 7.056 + 79.90 = 122.986 g/mol
• Bromobutane (C4H9Br):
  • 4 C: 4 x 12.01 g/mol = 48.04 g/mol
  • 9 H: 9 x 1.008 g/mol = 9.072 g/mol
  • 1 Br: 79.90 g/mol
  • Total = 48.04 + 9.072 + 79.90 = 137.002 g/mol

Arranging in Increasing Order

Now that we have the molecular weights, we can arrange the compounds in increasing order:

• Bromomethane: 94.934 g/mol
• Bromoethane: 108.95 g/mol
• Bromopropane: 122.986 g/mol
• Bromobutane: 137.002 g/mol

Thus, the increasing order of these compounds based on their molecular weights is:

Bromomethane < Bromoethane < Bromopropane < Bromobutane

This arrangement reflects the increasing number of carbon atoms and, consequently, the increasing molecular weight of the compounds. Each step up in carbon atoms contributes significantly to the overall weight due to the addition of both carbon and hydrogen atoms, along with the bromine atom.