Question

Hi everyone! Can someone solve these and explain them? I haven't solved any questions like these. Thank you!

You have a coffee cup calorimeter (isolated system, heat is measured at constant pressure mix two solutions (Ti-22.07 °C) in the coffee cup. Solution 1 is 50,0 mL - 50.0 B) of HI. Solution 2 is 50.0 mL (50.0 g) of UNKNOWN MOLARITY of LiOH. You kn the LiOH solution is the limiting reagent. Upon mixing the temperature of the mixture cup increases to 34.18°C. What is the concentration in M) of the original Lion red at constant pressure). You 30.0 mL - 50.0 g) of 2.00 M Additional information: HI(aq) + LiOH(aq) → H2O(l) + Lil(aq) AH =-56.4 kJ Specific heat (c) of the mixed solution - 4.18 Jg'°C. Specific heat of liquid water-4.18 Jg'°C 6. (10 pts) You find that you need light with wavelength of 162 nm to pull an electron off of a Mg atom. What is the electron binding energy (i.e. work function) of Mg in kJ/mol?

Answer 1

Angwer: B Total mass = so og+so.cg = 100. og Heat released, a= -mcat = -100.ogx 4:185/9°CX (34.18-22.07j°C - S061.98J Now 1 000 Hilaa) + Liomlag) HOH) + LiIlac) DH=-564 kJ for on=q = -56.4 KT neles of trom used = 1 mel . -56.4kJ = 1 mere troy - - S061-98 KJ = Imole LioH x-506198 kJ - 56.4KJ X1000 = 0.08975 mol Now moles of LIGH = Volume(L) x melarity (moilt) - 0.08975 mel = 0.OSOL x molarity of lion :. molasity of LiOH = 1.795m2. î 1.go my asever ③ 2 = 162x10-9 m (Inm= 1x10-9m) Evergy required to pull off an election from a mg atom = ne - 6:03 x1034 JS X 3 X108ms 7 162x10-9m = 1.23 x 1078 T latem Now I mal of mg conteons 6.022x10 23 atem for 1 mes & Everagey = 6.022x1023 atemx1.23x10-185/atem = 7.3936x105 J = 739.4 ks mei-l laseva