Samples of three different compounds were analyzed and the masses of each element were determined. Compound Mass N (g) Mass O (g

The correct answer is: c. N2O, N2O4, N2O5.

According to the law of multiple proportions, also referred to as Dalton's Law, when two elements form compounds, the mass ratios of the second element that combine with a specific mass of the first yield small whole number ratios.

1) For NO, the mass ratio m(N): m(O) is 14: 16, simplified to 7: 8.

2) In N₂O, the ratio m(N): m(O) equates to 2·14: 16, which simplifies to 7: 4.

3) For NO₂, the masses yield m(N): m(O) = 14: 2·16, simplifying to 7: 16.

4) In N₂O₅, the ratio is (2·14): (5·16), which simplifies to 7: 20.

5) For NO₄, the mass ratio is m(N): m(O) = 14: (4·16), which simplifies to 7: 32.

6) N₂O₄ gives a ratio of m(N): m(O) as (2·14): (4·16), simplifying to 7: 16.

A) This means m(N): m(O) = 5.6 g: 3.2 g, simplifying results in 1.75: 1, which further translates to m(N): m(O) = 7: 4.

B) Here, m(N): m(O) is 3.5 g: 8.0 g. Dividing reveals a ratio of 1: 2.285, which alters to m(N): m(O) = 7: 16.

C) Lastly, for m(N): m(O) = 1.4 g: 4.0 g, then adjustments yield a ratio of m(N): m(O) = 7: 20.

The possible formula in Dalton's time (had never heard of a mole)

a. NO₂, NO₈, NO₁₀

c. N₂O, N₂O₄, N₂O₅

Further explanation

Dalton's law of multiple proportions asserts that when two or more types of compounds emerge from the same elements, if one element's mass remains unchanged, the other element's mass in the different compounds will be expressible as a simple integer ratio.

An analysis of the samples reveals the mass ratio of nitrogen and oxygen in the following compounds:

• 1. Compound A: N: O = 5.6: 3.2 = 1.75: 1

• 2. Compound B: N: O = 3.5: 8.0 = 1: 2.235

• 3. Compound C: N: O = 1.4: 4.0 = 1: 2.8857

To reduce the numbers to simpler whole numbers, we multiply the ratio by 7, resulting in:

Compound A: 7: 4

Compound B: 7:16

Compound C: 7:20

This proportion clearly indicates that for every nitrogen atom, the ratios for oxygen are 4:16:20 = 1: 4: 5 (consistent with Dalton's theory)

Consequently, based on Dalton's views (which exclude the mole concept), the possible compounds can be:

a. NO₂, NO₈, NO₁₀

c. N₂O, N₂O₄, N₂O₅

If we apply the mole concept, which reveals the compounds' empirical formulas, the mole ratios of the compounds are as follows:

• Compound A:

5.6 / 14: 3.2: 16 = 0.4: 0.2 = 2: 1

• Compound B:

3.5 / 14: 8/16 = 0.25: 0.5 = 1: 2 = 2: 4

• Compound C:

1.4 / 14: 4/16 = 0.1: 0.25 = 2: 5

Thus, by utilizing the mole concept, the relevant compounds are c. N₂O, N₂O₄, N₂O₅

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A sample of H₂SO₄

Keywords: Dalton, the law of multiple comparisons