Atomic Theory Video Lessons

Concept: The Conservation of Matter

# Problem: Part A. Identify the statements that are correct.For two compounds of C and O, the mass ratio of C to O in one compound is a multiple of the mass ratio of C to O in the other compound or can be converted to a small whole number ratio.The mass ratio of oxygen to carbon in CO is 1.33 for every sample of CO.The mass ratio of oxygen to carbon in CO is twice the mass ratio of oxygen to carbon in CO2.The mass ratio of oxygen to carbon in CO2 is 2.667 for every sample of CO2.Check all that apply. The law of multiple proportions predates the concept of a mole or molar mass. Thus, scientists like John Dalton could only determine the relative amounts of each type of atom in a formula, and not the exact formula. For example, Dalton could determine that there were two carbon-oxygen compounds, one with twice as much oxygen as the other, but he could not know for sure what their formulas were. However, he could determine that the mass ratio of the elements in one compound was related to the mass ratio of elements in the other compound by a small whole number.If two elements A and B combine to form two compounds AB and AB2 then the ratio of the mass of B to A in AB2 and the mass of B to A in AB will be a simple whole number.When carbon reacts with a small amount of oxygen, the principle product formed is carbon monoxide (CO). When the oxidation occurs in a higher concentration of oxygen, the principle product formed is carbon dioxide (CO2). The mass ratio of oxygen to carbon in carbon dioxide (CO2) is twice the mass ratio of oxygen to carbon in carbon monoxide (CO).

###### Problem Details

Part A. Identify the statements that are correct.

• For two compounds of C and O, the mass ratio of C to O in one compound is a multiple of the mass ratio of C to O in the other compound or can be converted to a small whole number ratio.
• The mass ratio of oxygen to carbon in CO is 1.33 for every sample of CO.

• The mass ratio of oxygen to carbon in CO is twice the mass ratio of oxygen to carbon in CO2.

• The mass ratio of oxygen to carbon in CO2 is 2.667 for every sample of CO2.

Check all that apply.

The law of multiple proportions predates the concept of a mole or molar mass. Thus, scientists like John Dalton could only determine the relative amounts of each type of atom in a formula, and not the exact formula. For example, Dalton could determine that there were two carbon-oxygen compounds, one with twice as much oxygen as the other, but he could not know for sure what their formulas were. However, he could determine that the mass ratio of the elements in one compound was related to the mass ratio of elements in the other compound by a small whole number.

If two elements A and B combine to form two compounds AB and AB2 then the ratio of the mass of B to A in AB2 and the mass of B to A in AB will be a simple whole number.

When carbon reacts with a small amount of oxygen, the principle product formed is carbon monoxide (CO). When the oxidation occurs in a higher concentration of oxygen, the principle product formed is carbon dioxide (CO2). The mass ratio of oxygen to carbon in carbon dioxide (CO2) is twice the mass ratio of oxygen to carbon in carbon monoxide (CO).