The answer is 2.49 x 10^5 KJ. This was obtained (1) use the formula for specific heat to achieve Q or heat then (2) get the energy to melt the copper lastly (3) Subtract both work and the total energy required to completely melt the copper bar is achieved.
Answer:
- <u>The energy change would be 46kJ</u>
- <u>The energy would be absorbed</u>
Explanation:
The <em>energy change </em>during a chemical reation, i.e. the reaction energy, is equal to the chemical energy stored in the<em> bonds of the products </em>less the chemical energy stored in the <em>bonds of the reactants</em>.
Hence:
- <em>Energy change</em> = 478 kJ - 432kJ = 46kJ
The change is positive, this is, the chemical energy of the products is greater than the chemical energy of the reactants.
That corresponds to the second graph, where the level of the energy of the products in the graph is higher than the level of the energy of the reactants. Therefore, the conclusion is that the reaction <em>absorbed energy</em> and it is endothermic.
Answer:
1.
Firstly removing off one strip and it leaves electrons behind, so the strip becomes positively charged.
2. The roll however is not negatively charged because it is "earthed " by the hand holding it, thus excess negatives repel each other away through the hand.
3.Tearing off the next strip and once more it leaves electrons behind, the new strip is also positively charged and will repel the first strip.
4. Then, tear two strips apart and one will leave electrons behind on the other. Meaning that one strip is positive and the other is negative and they will attract each other.
Answer:
A nuclear winter is a climatic phenomenon that would follow the detonation of several atomic bombs in the event that a nuclear war broke out. These bombs would cause firestorms that would raise smoke, dust and particles into the atmosphere that would end up in the stratosphere and eventually spread throughout the globe.
Explanation:
That idea is far fetched, because even though those same particles would absorb sunlight, it would raise the temperature in the stratosphere and cause a decrease in temperature in the Earth's layer. Unable to seep the sun's rays, many plant species would die and this would affect the entire food chain.
In addition, that temperature rise in the stratosphere would destroy part of the ozone layer, causing greater exposure to ultraviolet rays. This would end up affecting health and further damaging plant species.
