anonymous one year ago If 45g of LiF dissolved in 1.8kg of water, what would be the expected change in boiling point? The boiling point constant for water (Kb) is 0.51 degrees C/m. - 0.49 degrees C - 0.98 degrees C - 1.9 degrees C - 3.5 degrees C Im not sure which one it is I got both 0.49 and 0.98 Please Help. I will medal.

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1. aaronq

What calculations did you perform?

2. anonymous

I ended up going with the first answer 0.49 based on my calculations

3. aaronq

did you have $$\large \Delta T=i*K_b*m=2*(0.51~^oC/m)*\dfrac{(\frac{45~g}{25.9~g/mol})}{1.8~kg}$$

4. anonymous

No and when I solve yours I get 25 which isn't a choice

5. aaronq

you're solving it incorrectly, because i get 0.984555984555984583356

6. anonymous

I'm so lost

7. anonymous

I don't know who's right

8. aaronq

I'm right lol you got 0.49 because you didn't take into account that i=2

9. anonymous

Okay thank you so much

10. anonymous

11. aaronq

no problem, and sure, shoot.

12. anonymous

A 65 gram of some unknown metal at 100.0 deg C is added to 100.8grams at 22 degrees Celsius. The temperature of the water rises 27.0 degrees C. Of the specific heat capacity of liquid water is 4.18 J/degC*g, what is the specific heat of the metal?

13. anonymous

The choices are -2.25 J/(C*g) -1.75 J/(C*g) -0.444 J/(C*g) -0.324 J/(C*g)

14. anonymous

I don't know Where to start @arronq and how to get the answer

15. aaronq

So this is a little complicated but bare with me. First you use the mass of the water, the specific heat capacity and the change of temperature the water had to find the heat lost by the metal. Now that you have the heat lost by the metal, you can use the mass of the metal and the temperature change of the metal (along with the heat you found in the first part) to solve for the specific heat capacity. The equation is $$\sf q=m*C_p*\Delta T$$ q= heat m=mass Cp=specific heat capacity $$\Delta T$$=change in Temp

16. anonymous

Based on what your saying and what I do know I'm getting 0.444 with my calculations. Is that correct?

17. aaronq

18. anonymous

I can't I don't have a camera and my computers to old to type them in

19. aaronq

so how am i supposed to see if you're doing it right?

20. anonymous

I think I am I just need to double check the final response with you and if I get it wrong I'll try it a different way until I'm doing it right

21. aaronq

its right

22. anonymous

Okay thank you so much

23. aaronq

no problem