How many moles of NAOCl are there in 3mL of bleach solution. The density of the solution is 1.005g bleach soln/mL and it is 5.25% by mass (5.25 NAOCl/100g soln.
Can someone tell me if I have this set up correctly?
3mL * 1.005g/1ml * 5.25g/100g* 1mol NAOCl/74.44g NAOCl
Thank you
I think that looks OK
....be consistent with mL or ml
....remember it is NaOCl
....and there is a space between the number and the unit.
but Hey I'm picky
Thank you I just wasn't sure I had the problem set up correctly. I appreciate the input. My professor is a bit picky as well :)
I learnt to be picky as a Prof myself, perhaps it goes with the job?
Good luck.
Yes, being detail-oriented and precise is important when it comes to scientific calculations. In this case, your setup looks correct. Let me explain the steps to arrive at the answer for your question.
The given information states that the density of the bleach solution is 1.005 g/mL and it is 5.25% by mass NAOCl (or 5.25 g NAOCl per 100 g of solution).
To calculate the number of moles of NAOCl in 3 mL of the bleach solution, you need to follow these steps:
Step 1: Convert the volume of the bleach solution from mL to grams using the given density.
3 mL bleach solution * 1.005 g bleach solution / 1 mL bleach solution = 3.015 g bleach solution
Step 2: Use the mass percent of NAOCl to calculate the mass of NAOCl in the given amount of bleach solution.
3.015 g bleach solution * (5.25 g NAOCl / 100 g bleach solution) = 0.1581375 g NAOCl
Step 3: Convert the mass of NAOCl to moles using its molar mass.
0.1581375 g NAOCl * (1 mol NAOCl / 74.44 g NAOCl) ≈ 0.002124 moles NAOCl
So, there are approximately 0.002124 moles of NAOCl in 3 mL of bleach solution.
Remember, it's always good practice to double-check your work and make sure your units cancel out properly.