Answer:
Examples of physical change include changes in the size or shape of matter. Changes of state—for example, from solid to liquid or from liquid to gas—are also physical changes. Some of the processes that cause physical changes include cutting, bending, dissolving, freezing, boiling, and melting.
Explanation:
The general formula for the alkenes is C nH 2n
Answer:
0.05 mol
Explanation:
Moles = Mass / Mr (Relative formula mass)
Ar of aluminium = 27
Ar of sulphur = 32
Ar of oxygen = 16
Mr of Al2(S2O3)2 = (27×2)+((32×2)×3)+((16×3)×3)= 390
Moles = 18.5g / 390
Moles = 0.05 mol
the answer is C
It is a chemical change because heat energy is absorbed and the pack gets colder. A change in temperature is a sign that a chemical reaction has taken place; increase in temperature is an exothermic reaction and decrease in temperature is an endothermic reaction. This is an endothermic chemical reaction.
