Chem 1 chapter 2.1

What scientist is credited with conducting experiments that led to the law of definite proportions?

Joseph Proust is credited with the formulation of the law of definite proportions.

If 1 mole of water has a ratio of 1:8 of hydrogen to oxygen by mass, then what will the ratio be for 2 moles of water?

1:8 The ratio will always be 1:8 for any size sample according to the law of definite proportions.

A 100 g sample comprised of molecule (A) is made up of 57.1 g of oxygen and 42.9 g of carbon. Another 100 g sample comprised of molecule (B) is made up of 72.7 g oxygen and 27.3 g carbon. The ratio of oxygen: carbon mass ratios between the two molecules is 2:1. Which law is demonstrated in this calculation?

the law of multiple proportions The law of multiple proportions states that when two elements react to form more than one compound, a fixed mass of one element will react with masses of the other element in a ratio of small, whole numbers.

What law states that when two elements react to form more than one compound, a fixed mass of one element will react with masses of the other element in a ratio of small, whole numbers?

the law of multiple proportions The law of multiple proportions states that when two elements react to form more than one compound, a fixed mass of one element will react with masses of the other element in a ratio of small, whole numbers.

If 8.0 grams of oxygen react with 1.0 grams of hydrogen to generate a sample of water, then how many grams of hydrogen will 16.0 grams of oxygen react with to form a sample of water?

2.0 grams The law of definite proportions tells us that it we double the amount of oxygen, we must also double the amount of hydrogen, since the ratio by mass of the elements in water will be constant.

One 100 g sample comprised of molecule (A) is made up of 57.1 g of oxygen and 42.9 g of carbon. Another 100 g sample comprised of molecule (B) is made up of 72.7 g oxygen and 27.3 g carbon. What is the ratio of these oxygen:carbon mass ratios?

2:1 In molecule A: 57.1 g O/42.9 g C= 1.33 g O per g C In molecule B: 72.7 g O/27.3 g C= 2.66 g O per g C So the ratio between them is 2.66/1.33=2.

On a camping trip to the mountains, you use 7/8 of a tank of gas to travel 3/4 of the way to the mountains. How many tanks of gas will you need to travel 5/7 of the entire distance to the mountains? Give your answer as a simplified fraction, and do not include the units.

5/6 Setting up the proportion, we find 7/8 tank of gas/3/4 distance= x tank of gas/57 distance Now, cross multiplying, we find 7/8x5/7=3/4xX Now, multiplying both sides by 4/3 to cancel the fraction, and simplifying, we find that =5/6

A 100 g sample of substance A is composed of 57.1 g of oxygen and 42.9 g of carbon. Another 100 g sample of substance B is made up of 72.7 g oxygen and 27.3 g carbon. What can be determined about substances A and B?

Substances A and B are composed of different compounds, with B having twice the mass ratio of A If the two substances were composed of the same compound, then their mass ratios of oxygen-to-carbon would be the same.

Dalton's atomic theory served to explain:

he law of conservation of matter the law of definite proportions the law of multiple proportions answer : all of the above It was the ability of Dalton's theory to explain all of the above observations that made it so powerful in changing the landscape of chemistry in the early 19th century.

A sample of compound A (a clear, colorless gas) is analyzed, and found to contain 4.27 g carbon and 5.69 g oxygen. A sample of compound B (also a clear, colorless gas) is analyzed, and found to contain 5.19 g carbon and 13.84 g oxygen. Are these data an example of the law of definite proportions, the law of multiple proportions, or neither?

law of multiple proportions