What's your question? Am I missing something?
I think it is C, because a covalent bond is a distribution of 2 atoms to 1 electron, meaning they are sharing and not exchanging, and the electronegravity would be above 1.7
Use the Heat formula for both problems.
q=m*c*∆t
Where
q= heat in Joules
m= mass in grams
c= specific heat which is a constant 4.18
∆t= change in temperature
1,05+ 0,69 + 1,82 = 3,56g of mixture
%CaCO₃: 1,82/3,56×100% = 0,5112×100% = 51,12%
