chemistry - conc. of solutions

I have a question 'calculate the number of moles of colute in the following solutions:
a. 250cm^3 of 1.00mol dm^3 sodium hydroxide
my answer= 1.00x250 / 1000= 0.25 moles. I was wondering if that is all i have to do. Do i need to use the Mr of sodium hydroxide in any way? Or is it that i just need to find the moles.
For question 3 I need to find the mass so then would i do the 0.25 x Mr Sodium hydroxide?
Thanks xxx

Reply 1

Jez_249

yeh, you're sorted... well its what id do.. so i hope you're right, lol.. and im in yr 13

Jez

Reply 2

indie_couture

Jez_249

yeh, you're sorted... well its what id do.. so i hope you're right, lol.. and im in yr 13

Jez

Okay, Thanks! xxxxx

Reply 3

Jez_249

no worries... you know what you're doing from what i can see... why so unsure oof yourself??

Jez

Reply 4

indie_couture

Jez_249

no worries... you know what you're doing from what i can see... why so unsure oof yourself??

Jez

just surprised i'd actually got it and it didnt seem hard! xxx

Reply 5

Sanjetti

Spot on

Mr only comes into play when you're calculating no. of moles when MASS is involved.

Reply 6

Jez_249

indie_couture

just surprised i'd actually got it and it didnt seem hard! xxx

Haha, try not to overcomplicate things.. i always do that!!
Just wait till you start doing chemistry coursework.. that really is overcomplicated.. for me anyway.. but easy for others :biggrin:

Jez

Reply 7

Aaron_1507