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snehra1
Jan 20, 2007, 05:27 PM
HI,

Here is my question,please reply me as early if possible.

.250g sample of mettalic Sodium is carefully dropped into a mixture of 10g of ice and 10g of water at 0 degree Celsius the reaction is 2Na+2H2O------- H2+2oH+2Na deltaH=-368.0KJ. If the resultant mixture has a specific heat of 4.18 J/g*degree Celsius.

Calculate the final temperature of mixture deltaH fusion=6.01KJ/mol

thanks
waiting for a positive reply asap.

J_9
Jan 20, 2007, 05:29 PM
Please tell us what you think will happen. We will help you from there, but we cannot in good conscience do it for you.

You will not learn if someone does your homework for you.

snehra1
Jan 20, 2007, 05:41 PM
Please tell us what you think will happen. We will help you from there, but we cannot in good conscience do it for you.

You will not learn if someone does your homework for you.
Ok,

According to what I think is deltaH= heat of reaction q

and q=mCdeltaT (mass,specific heat,temperature)

so q= -368 KJ=-360*1000 j
C= 4.18 /g/c

m= I am wondering about this mass only I mean what mass I sholud mention here,mass of ice i.e. 10g only or total mass of ice,water and sodium

then by putting all the values on equation q=mcdeltaT

we can find out delta T that is equal to t final - t initial and t initial=0 degree Celsius

so from here by subtracting tinital from deltaT we can find out final temperature.
So, guide me now weather I am on right way and what mass I should use.

thanks so much

Capuchin
Jan 22, 2007, 12:59 AM
Hi, you are heating up the whole solution, so you must use the whole mass.

Everything you have written looks okay to me, although I haven't had time to read through it completely.
Good luck!