Can you please answer Qustions 7 & 9 Please .. i need it urgently 7.(Ipt) Write

Question

Can you please answer Qustions 7 & 9 Please .. i need it urgently

7.(Ipt) Write the net ionic equation for the reaction below: (Hint- you need to figure out which of the reactants and products are strong electrolytes) H102(aq) + KOH(aq) KI(aq) H20(1) + Ca4) 8) (1pt) Use dimensional analysis to calculate the number of H atoms in 1 mole ofCsH/ molex 2 9) (3 pts)Determine the empirical and molecular formula of caffeine which contains O 49.5% C, 5.15% H, 28.9% N by mass and has a molar mass of 195 g/mol. 5.5% / 21.17 12 6.02 6-4 2 :, 35 2.0 O4.35

Explanation / Answer

Molecular reaction is HIO2(aq)+ KOH ----------> KI(aq)+ H2O(l)

H++IO2- + K+ +OH- -------->K++I-+ H2O(l) ionic equation

H++OH- --------->H2O(l) net ionic equation

2.   atomic weights : C= 12, H= 1 and O= 16 and N= 14

Basis :100 gm of caffeine, it contains 49.5 gm of C, 5.15gm of H, 28.9 gm of N and 100- (49.5+5.15+28.9)= 16.45 O

molar ratio of C: H: N: O= 49.5/12: 5.15/1 : 28.9/14: 16.45/16= 4.125: 5.15: 2.06: 1.03

dividing by 1.03, the lowest no, molar ratio of C: H:N:O= 4.125/1.03 : 5.15/1.03 : 2.06/1.03 :1

4:5:2:1

empirical formul is C4H5N2O

molar mass of empirical formula is 4*12+5+28+16= 97 g/mole

n* molar mass of empirical formula= 195 , molar mass

n*97 = 195

n= 2

hence molecular formula is C8H10N4O2.

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