For #1, I'd say it's "It will usually bond to multiple atoms which can provide a total of 4 additional electrons."
2. Ionic (I'm quite certain because anions/cations (-1 & +1) are Ionic from what I recall, if that's true it's Ionic.
3. "comparison of the associated families to which the elements belong" and
"the difference in electronegativities" are what I would choose, as I mentioned in a comment earlier.
If I'm wrong let me know, but I am at least 80% sure that these responses are correct from what I remember in Chemistry.
When 0.514 g of biphenyl (C12H10) undergoes combustion in a bomb calorimeter, the temperature rises from 25.8 C to 29.4 C. Find ⌂E rxn for the combustion of biphenyl in kJ/mol biphenyl. The heat capacity of the bomb calorimeter, determined in a separate experiment, is 5.86 kJ/ C.
<span>The answer is - 6.30 * 10^3 kJ/mol
</span>
Explanation:
The pH is a 1 to 14 scale that measures how acidic or basic is a solution, at lowest number the solution will be acid, in 7 the solution will be neutral, and in higher values will be basic. It is a logarithmic scale, so with each number you move, the acidity or basicity will be increased by a factor of 10. So, lemon juice is more acidic than orange juice by a factor of 100.