If you have a book, read it!! I promise you, it tells you this answer!
Answer:
The answer is option a. The evaporation of water from the skin
Explanation:
An endothermic reaction is any synthetic reaction that retains heat from its environment. The ingested energy gives the enactment energy to the reaction to happen.
No new bonds formed, no bonds broken in this example. water molecules go from liquid to vapour (gas ), intermolecular bond exist between polar (-OH) molecules and energy is required to break these bonds during the change from liquid to gas. So, it is endothermic .
Remaining three above examples are exothermic. combustion of gas releases energy(exothermic). burninig of the candle exothermic because the energy released from the oxygen into carbon dioxide and water.oxidation of iron also exothermic
Answer: C= 0.406 M
Explanation:
Solution.
ν
=
0.730
m
o
l
;
ν=0.730mol;
V
=
1.8
⋅
1
0
3
m
L
=
1.8
L
;
V=1.8⋅10
3 mL=1.8L;
C=0.730mol
1.8 L=0.406 M
C= 1.8L
0.730mol =0.406M
The student made a mistake because he did not convert a unit of volume from milliliters to liters. After all, molarity is defined as the number of moles of solute per liter of solution.
