Answer:
Electric engines have efficiencies of roughly 90% whilst combustion engines about 10% to 30%. This is because combustion engines emit much more heat, which is always energy that is not used as work, and thus increases inefficiency.
Explanation:
The change of the statue of liberty from copper to green is an example of a chemical change.
<h3>Physical and chemical change</h3>
A physical change does not involve the formation of new substances and the composition of the substance does not change. However, in a chemical change, a new substance is formed and the composition of the substance changes.
The statement that reflect a chemical change is;
- The Statue of Liberty’s metal tarnishes from copper to green.
Learn more about physical and chemical change: brainly.com/question/13316655
Quantity of K2S m = 0.105 m
Number of ions i = 2(K) + 1(S) = 3
Freezing point depression constant of water Kf = 1.86
delta T = i x m x Kf = 3 x 0.105 x 1.86 = 0.586
Freezing point = 0 - 0.586 = 0.586 C
Boiling point constant of water Kb = 0.512
delta T = i x m x Kb = 3 x 0.105 x 0.512 = 0.161
Boiling point = 100 + 0.161 = 100.161 C
