A compound frequently used as a high-temperature lubricant has the formula MS2, where M represents some metallic element. If this compound is 40.06% sulfur by mass, what is the identity of the metal M?
I'm confused on how to figure this out.
Calculate the pH of each solution given the following or values:
a. [H3O+] = 1 * 10-8M
b. [H3O+] = 5 * 10-6M
c. [OH-] = 4 * 10-2M
d. [OH-] = 8 * 10-3M
e. [H3O+] = 4.7 * 10-2M
f. [OH-] = 3.9 * 10-6M
To determine the identity of the metal M in the compound MS2, we can use the concept of percent composition. The percent composition calculates the mass percentage of each element in a compound.
First, let's assume we have 100 grams of the compound MS2. Since the compound is 40.06% sulfur by mass, we can determine the mass of sulfur present in 100 grams of the compound:
Mass of sulfur = (40.06/100) x 100 grams
Mass of sulfur = 40.06 grams
Next, we need to find the mass of the metal M in the compound. To do this, we subtract the mass of sulfur from the total mass of the compound:
Mass of M = Total mass of the compound - Mass of sulfur
Mass of M = 100 grams - 40.06 grams
Mass of M = 59.94 grams
Now, we need to find the molar mass of M (MM). The molar mass is the mass of one mole of a substance. To determine the identity of the metal M, we should compare the molar mass of M to the molar mass of known elements.
Using the periodic table, we can find that the closest molar mass of a metallic element to 59.94 grams/mol is that of cobalt (Co). The molar mass of cobalt is approximately 58.93 grams/mol.
Therefore, based on the percent composition analysis, the metal M in the compound MS2 is most likely cobalt (Co).
To determine the identity of the metal M in the compound MS2, you need to use the concept of percent composition. The percent composition of an element in a compound is the mass of that element divided by the total mass of the compound, multiplied by 100.
Here's how you can solve the problem step by step:
1. Assume that you have a 100g sample of the compound MS2.
2. From the given information, you know that the compound is 40.06% sulfur by mass.
3. Calculate the mass of sulfur in the sample by multiplying the sample mass (100g) by the percent composition of sulfur (40.06%):
Mass of sulfur = 100g * (40.06/100) = 40.06g.
4. To find the mass of the metal M, subtract the mass of sulfur from the total mass of the compound:
Mass of metal M = 100g - 40.06g = 59.94g.
5. Now, you know that the compound MS2 has 59.94g of metal M and 40.06g of sulfur.
6. Use the atomic masses of the elements to find the molar ratio between metal M and sulfur. The atomic mass of sulfur (S) is 32.07 g/mol, and the atomic mass of metal M is not given.
7. Assume that the compound MS2 has one atom of metal M and two atoms of sulfur (based on the subscript 2 in the formula).
8. Calculate the number of moles of sulfur in the compound:
Moles of sulfur = Mass of sulfur / Atomic mass of sulfur = 40.06g / 32.07 g/mol = 1.249 mol.
9. Since there is a 1:2 molar ratio between metal M and sulfur, you can conclude that the number of moles of metal M is half the number of moles of sulfur:
Moles of metal M = 1.249 mol / 2 = 0.6245 mol.
10. Finally, to determine the identity of the metal M, you need to find an element with a molar mass close to 59.94 g/mol (or half the molar mass of sulfur), which is approximately 30 g/mol.
After considering the periodic table, you will find that the element with an atomic mass close to 30 is zinc (Zn). Therefore, based on the given information, the identity of the metal M in the compound MS2 is zinc.