A series or list of substances which can be arranged in the order of relative reactivity is termed asactivity series. For ex., hydrogen ions can be knocked out of the solution by magnesium metal; therefore magnesium is more reactive as compared to element hydrogen. The Activity Series of the metals is a invaluable aid to predicting the products of replacement reactions. It also can be used as an aid in predicting product of some other reactions. Pay attention to the notes below as they are provided to help you make better use of the activity series than just the list of metals by themselves
Mg(s) + 2 H+(aq) H2(g) + Mg2+(aq)
A series of elements that have similar properties—for example, metals—arranged in descending order of chemical activity.
The Activity Series of the metals is an invaluable aid to predicting the products of replacement reactions. It also can be used as an aid in predicting products of some other reactions. Pay attention to the notes below as they are provided to help you make better use of the activity series than just the list of metals by themselves.
1.Each element on the list replaces from a compound any of the elements below it. The larger the interval between elements, the more vigorous the reaction.
2.The first five elements (lithium - sodium) are known as very active metals and they react with cold water to produce the hydroxide and hydrogen gas.
3.The next four metals (magnesium - chromium) are considered active metals and they will react with very hot water or steam to form the oxide and hydrogen gas.
4.The oxides of all of these first metals resist reduction by H2.
5.The next six metals (iron - lead) replace hydrogen from HCl and dil. sulfuric and nitric acids. Their oxides undergo reduction by heating with H2, carbon, and carbon monoxide.
6.The metals lithium - copper, can combine directly with oxygen to form the oxide.
7.The last five metals (mercury - gold) are often found free in nature, their oxides decompose with mild heating, and they form oxides only indirectly.
A disaster interrupts the functioning of a society. Disasters have many forms from natural to human intervention induced. Natural disaster includes earthquake, landslide, hurricane, tornado, eruptions of volcanoes, fires / wild fire, flood and cyclones, etc. Human induced disasters include wars, deforestation, unplanned growth or constructions and other actions affecting life. A disaster affects natural life adversely by killing thousands of people and other lives. It also destroys a wide range of habitat and property. Chances of natural disasters are more in highly populated areas and environment get negative impacts by increased population density. Disaster prone areas become even more vulnerable to disasters by increased human interventions and less precautions for disaster management.
Disasters to be managed can be of various types like –
Earthquake, volcano eruptions and land slides are of geophysical origin.
Flood, wild fire, cyclone, tornado, drought and locust are of climatic origin.
Disaster management deals with preparing for these disasters and trying to stop these disasters to occur. It might not sound feasible to control nature to prevent occurrence of natural disasters but steps could be undertaken to reduce the effects of these disasters by formulating proper disaster management programme and reduce its affect on humans, other living things, property and economy as a whole.
Role of Students in Disaster Management - Training for Students
When the students are trained well, they can help in rehabilitation and resettlement of victims at times of floods, earthquakes and drought etc., .They can play a very important role in disaster management. They can spread awareness to all about the precautions to be taken at times of these national disasters. They will help the victims with basic needs and they will do whatever they can at times of these disasters. It is the duty of the teachers and school management to let them understand their duties and responsibilities during and after the disasters. This will minimise the panicking and uncontrolled disaster to the most extent. We should have to train them with the knowledge of basic first aid to save lives of millions. Hence, I feel students play a very important role in disaster management .
Let us learn about "Parts Of A Wave"
