I..don't understand any of this:
43. How many moles are in 25.0 grams of potassium? Show your work and round your answer to the appropriate number of significant figures.
Please, please help with this!
Thanks
-MC
moles = grams/molar mass
How do I figure out the molar mass?
-MC
Look up the atomic mass of each element and add.
molar mass NO = about 30.
N = 14 is atomic mass.
O = 16 is atomic mass.
total = 30 = molar mass.
No problem, I can help you with this question!
To find the number of moles in a given mass of a substance, we need to use the concept of molar mass. Molar mass is the mass of one mole of a substance and is expressed in grams per mole (g/mol).
First, we need to determine the molar mass of potassium (K). According to the periodic table, the atomic mass of potassium is approximately 39.10 grams per mole.
Next, we can set up a proportion using the given mass of potassium (25.0 grams) and the molar mass of potassium (39.10 g/mol):
(25.0 g potassium) / (39.10 g potassium per mole)
Now, we can solve the proportion to find the number of moles of potassium:
(25.0 g potassium) * (1 mole potassium / 39.10 g potassium) ≈ 0.639 moles
Therefore, there are approximately 0.639 moles of potassium in 25.0 grams of potassium. Make sure to round your answer to the appropriate number of significant figures as specified in the question.
I hope this explanation helps! Let me know if you have any further questions.