A 200.0 g sample of a pure substance was composed of 134.1 g of copper and 65.9 g of sulfur. Another sample of the same substance, this time with a mass of 150.0 g, was brought to Joseph Proust to analyze. How many grams of copper and sulfur would you expect to find in the sample?
copper

Enter a number with the correct number of significant figures.

1 g
sulfur

Enter a number with the correct number of significant figures.

2 g

What basic law in chemistry are you employing in order to make your determination?

Fill in the missing information for a compound consisting of sodium and oxygen, assuming that is composed of a fixed ratio of sodium to oxygen of 1.44 : 1.00.

Fill in the information missing from the following table. (Type your answer in the "charge" column using the format +1, -2, and 0.)

isotope	protons	neutrons	electrons	charge
calcium-40	20	Answer is not case sensitive. 1	18	Answer is not case sensitive. 2
3 ---Select--- phosphorus-31 oxygen-16 sulfur-32	15	16	Answer is not case sensitive. 4	-3
silicon-28	Answer is not case sensitive. 5	14	14	Answer is not case sensitive. 6

Which of the following are represented by the charge? (Select all that apply.)

Arrange these atoms in order of their quantity of protons (least number to greatest number): fluorine, sodium, magnesium, copper, nickel, carbon, beryllium.
1 ---Select--- fluorine sodium magnesium copper nickel carbon beryllium < 2 ---Select--- fluorine sodium magnesium copper nickel carbon beryllium < 3 ---Select--- fluorine sodium magnesium copper nickel carbon beryllium < 4 ---Select--- fluorine sodium magnesium copper nickel carbon beryllium < 5 ---Select--- fluorine sodium magnesium copper nickel carbon beryllium < 6 ---Select--- fluorine sodium magnesium copper nickel carbon beryllium < 7 ---Select--- fluorine sodium magnesium copper nickel carbon beryllium

Write nuclide notation for each of the following isotopes. (Enter the first (raised) number in the first box, the second (lower) number in the second box, and the symbol of the element in the third box.)

The element neon is widely used in brightly colored electronic advertising signs. There are three common isotopes of neon with masses of 21.99, 20.99, and 19.99. One of the three isotopes makes up approximately 90% of the atoms in a neon sample. Which isotope is most likely to be responsible for the majority of neon's atomic mass reported on the periodic table?

Give the average atomic mass to support your answer.

Enter a number with the correct number of significant figures.

2 amu

In each of these examples, determine the correct empirical formula. (Type your answer using the format CO2 for CO₂.)