How do I prepare a 10 ppm solution of riboflavin in water?

Question

anonymous · Answer

Hi! It's been almost two years since I've had a lab and I can't remember how to convert this to figure out how much riboflavin I need to add to make a stock solution.

cuanchi · Answer

ppm = mg/L  then 10mg of riboflavin + 1 L of water

anonymous · Answer

So, .01 grams of Riboflavin to 1000ml of water

anonymous · Answer

What about a 100 ppm solution of pyroxidane in 1% acetic acid?

cuanchi · Answer

NO!, 0.001g

anonymous · Answer

why .001g?

cuanchi · Answer

1g=1000mg

cuanchi · Answer

100mg of pyroxidane + 10 mL of acetic + 990 mL water

anonymous · Answer

Ok, I understand that. Thank you! Would you mind if I asked you a few more question? How would you prepare a 10 ppm Vitamin B solution. Is it the same as what we just did? 10 ppm = 10 mg/L = 0.001g + 1L?

cuanchi · Answer

I will mix the water with the acetic firs and then dissolve the compound in that or made a stock solution  more concentrated

cuanchi · Answer

Yes it is the same

anonymous · Answer

Okie, got it! Thank you! Also, last one, I promise, how would you prepare a 1 ppm solution from a 10 ppm Vitamin B solution?