## anonymous 3 years ago how many molecules of glucose are in a 2.0 mL of a 1.02 mM solution of glucose

1. aaronq

find the amount of moles using the formula for molarity: Molarity = moles/Liters of solution then multiply the number of moles by avogadros number

2. aaronq

ps. convert to mM to M. 1 mM = 0.001 M

3. anonymous

so calculate the mass C6H12O6? then divide that by 1.02?

4. aaronq

no, you don't need the molar mass since you're not converting to grams

5. anonymous

i'm just lost on the moles then how do i find that

6. aaronq

with the molarity and the volume of solution given

7. aaronq

molarity is a form of expressing concentration (in terms of moles per liter).. so basically by multiplying the molarity by the volume, you find the moles but you have to covert to molarity because mM meaning millimolar, 1 molar = 0.001 millimolar

8. anonymous

so like $\frac{ 2mL }{ 1mm} X \frac{ 1mm }{ 0.001 } ?$

9. aaronq

nope convert volume to liters .. 2mL = 0.002 L convert millimolarity to molarity 1.02 mM = 0.00102 M 0.00102 M x 0.002 L =

10. anonymous

2.04X10^-6

11. aaronq

looks right, i don't have a calculator around to check though

12. anonymous

ok thank you so much

13. aaronq

no problem

14. aaronq

ps you still need to multiply by avogadros number

15. anonymous

yea i figured that I'm trying to get a better number I would take that equations answer 2.04 ... and multiply it by avogadro's number right

16. aaronq

yep, it's 2.04x10^-4 though don't forget

17. anonymous

why 10^-4 i got -6

18. aaronq

sorry -6 lol my mistake

19. anonymous

haha its ok thank you again

20. aaronq

lol no prob, good luck