A sample containing .347 moles of an element has a mass of 39.00 g. What is the element?
Well, if you have a mole problem and you're looking for an element, I hope it's not mole-ybdenum, because that would be really hard to find. In this case, we can use the periodic table to solve the mystery. The atomic mass of the element in this sample is 39.00 g/mol, which means it has an atomic mass of 39.00 amu. So, based on that, I can confidently say that the element is potassium (K)! Hope that answer wasn't too "elementary" for you!
To determine the element, we need to find the molar mass of the element.
The formula to calculate the molar mass is:
Molar mass = Mass / Number of moles
Given that the mass of the sample is 39.00 g and the number of moles is 0.347 moles, we can rearrange the formula to solve for the molar mass:
Molar mass = (Mass / Number of moles) = 39.00 g / 0.347 moles
Molar mass = 112.48 g/mol (rounded to two decimal places)
To identify the element, we can compare the molar mass (rounded to two decimal places) to the periodic table. The element with a molar mass closest to 112.48 g/mol is cadmium (Cd). Therefore, the element in the sample is cadmium (Cd).
To determine the element, we need to calculate the molar mass of the sample and determine which element has that molar mass.
The molar mass of a substance is the mass of one mole of that substance. It is expressed in grams per mole (g/mol). We can calculate the molar mass using the formula:
Molar mass (g/mol) = Mass of the sample (g) / Number of moles
In this case, the mass of the sample is given as 39.00 g, and the number of moles is given as 0.347 moles.
Using the formula, we can calculate the molar mass:
Molar mass = 39.00 g / 0.347 moles
Molar mass ≈ 112.47 g/mol
Now that we have calculated the molar mass of the sample, we can compare it to the molar masses of known elements to identify which element it corresponds to.
Consulting a periodic table or using a molar mass calculator, we find that the element with a molar mass close to 112.47 g/mol is Cesium (Cs).
Therefore, the element in the sample is Cesium (Cs).
create a proportion to find out how much one mole weighs
.347moles = 39.00g
1 mole = ?
now just cross multiply and solve whatever you get for the weight you can match it to one on the periodic table with that molar mass since the mass listed on the periodic table is the mass of one mole of an element in grams.
you should get around 112.392g and i think