Number of atoms in the following samples of substances is the largest in:a)4.0 g of hydrogenb)71.0 g of chlorinec)127.0 g of iodined)48.0 g of magnesiumCorrect answer is option 'A'. Can you explain this answer?

Question

Answer

Explanation:

The number of atoms in a sample of a substance can be calculated using Avogadro's number (6.022 x 10^23) and the atomic/molecular weight of the substance.

For example, to calculate the number of atoms in 4.0 g of hydrogen:

Find the atomic weight of hydrogen (1.008 g/mol).

Calculate the number of moles in 4.0 g of hydrogen (4.0 g / 1.008 g/mol = 3.97 mol).

Multiply the number of moles by Avogadro's number to find the number of atoms (3.97 mol x 6.022 x 10^23 atoms/mol = 2.39 x 10^24 atoms).

Repeat this process for each substance:

71.0 g of chlorine has a molecular weight of 35.45 g/mol, so there are 2.00 mol in the sample. Therefore, there are 1.20 x 10^24 atoms in the sample.

127.0 g of iodine has a molecular weight of 126.90 g/mol, so there is 1.00 mol in the sample. Therefore, there are 6.02 x 10^23 atoms in the sample.

48.0 g of magnesium has an atomic weight of 24.31 g/mol, so there are 1.97 mol in the sample. Therefore, there are 1.18 x 10^24 atoms in the sample.

Comparing the results, we can see that the sample with the largest number of atoms is 4.0 g of hydrogen, with 2.39 x 10^24 atoms.

Answer

1mole represents 6.023 × 10*23 particles for example 1mole of hydrogen atom= 6.023 × 10*23 atoms of hydrogen=1.008g or nearly 1g of hydrogen atom it is given that 4g of hydrogen atom will be equal to 4 × 6.023 × 10*23 no. of atoms of hydrogen= 4 moles of hydrogen atom. 1 mole of chlorine atom= 6.023× 10*23 no. of chlorine atom = 35.5g of chlorine atom but it is given 71g of chlorine atom=2× 6.023× 10*23 no. of chlorine atom=6.023×10*23 no..of chlorine molecule or 2 moles of chlorine atom. 1mole of iodine atom= 6.023×10*23 no. of iodine atom=127.0g of iodine. 1mole of magnesium =24g of Mg=6.023×10*23no.of Mg it has given 48g of Mg=2×6.023×10*23 no. of Mg=2moles of Mg.. Hence we are concluded that 4g of hydrogen atom has largest no. of atoms.

Answer

A

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