Answer:
C. the solid dissolves after it is added to the liquid
Explanation:
Why, you may ask? Because endothermic reactions absorb energy by undergoing change. And that solid, just absorbed energy.
When something melts, the molecules inside the substance receive more and more energy, until the substance's molecules have enough energy to vibrate and wiggle past each other, breaking their structure. if the solid is receiving more energy from its surroundings, aka the liquid, the reaction is in fact absorbing energy. And if a reaction is absorbing energy, it's an endothermic reaction.
The fluid filled area between the pleural layers is called the pleural cavity.
I think it's 11.56 minutes
1) in periodic acid (HIO₄), iodine has oxidation number +7, hydrogen has oxidation number +1, oxygen has -2, compound has neutral charge:
+1 + x + 4 · (-2) = 0.
x = +7.
2) in molecule of iodine (I₂), iodine has oxidation number 0, because iodine is nonpolar molecule.
3) in sodium iodide (NaI), iodine has oxidation number -1, sodium has oxidation number +1:
+1 + x = 0.
x = -1.
4) in iodic acid (HIO₃), iodine has oxidation number +5, hydrogen has oxidation number +1, oxygen has -2, compound has neutral charge:
+1 + x + 3 · (-2) = 0.
x = +5.
