Answer:
6.9 (two sig figs)
Explanation:
2.375 + 4.5 = 6.875 = 6.9
When adding or subtracting, sig figs are determined by the least number of digits past the decimal point.
For the first question, the correct answer among the choices listed is option A, a chocolate bar melting in hot car. It is an endothermic process because it absorbs heat energy for it to be melted. For the second question, it think the correct answer is the last option, <span>(-2222) + (-1182) - (-1144).</span>
The answer is <span>ionic aluminum fluoride (</span>AlF3). Note that boiling points of pure solvents are raised in the presence of solutes. The type of solute also affects the boiling point elevation of the solution. Ionic substances tend to raise it more than covalent ones, so sucrose is out of the picture. Next, consider the number of ions the ionic substance produces. The more ions, the greater the BPE. AlF3 dissociates into 4 ions.
