Question

The element radium was discovered by Madam Curie. She was successful in isolating 0.2 g of the element from mineral pitch blende. For this work, she was awarded the Nobel Prize in chemistry in 1911. In her honor, UNESCO declared the year 2011 as international year of chemistry. The discovery of radium opened a new field of radioactivity and thereafter many new radioactive elements have either been isolated from natural sources or have been prepared artificially in the laboratory by nuclear Reactions. Radioactive materials are extensively been used for power generation and in the diagnosis and treatment of many diseases. In spite of these benefits, radiation leakage from nuclear plants causes severe health hazards to the mankind. Further atomic bombs (which were dropped by USA in Hiroshima and Nagasaki in japan in august in 1945) and other weapons of mass destruction use radioactive materials. 

Now answer the following questions. 

(i) Name the group and period of the periodic table in which radium lies. 

(ii) Name a few other radioactive elements which have been prepared in the lab. 

(iii) Name two radioactive materials which have been used for treatment of cancer. 

(iv) In view of the nuclear power plant disasters which occurred in 3 Mile-Island (USA), Chernobyl (Ukraine), Fukushima (Japan) etc. should the nuclear power generation be stopped? Give your suggestions.

Answer 1

(i) Radium - Group 2, Period 7. It is the last element of the alkaline earth family. 

(ii) Tc (Technetium), Po (Polonium), U (Uranium) and all the transuranic elements from ₉₃Np to ₁₀₃Lr. Notable amongst these is Plutonium (₉₄Pu) which is extensively being used in power plants. 

(iii) ₈₈Ra ²²⁶ and ₂₇CO⁶⁰ are widely used for treatment of cancer. 

(iv) The three main sources of power are : Fossil Fuels, Hydroelectric power, and atomic power, in view of the depleting stocks of fossil fuels and hydroelectric power limited by landscape, the only alternative is Atomic Power. But nuclear power plants have serious disadvantages. Elaborate and expensive safety, precautions must be taken to protect plant workers and the residents of the surrounding areas from radiation. The nuclear reactor must be heavily shielded and housed inside a building made of metal and concrete. Since loss of coolant water can result in the meltdown of the reactor core, backup emergency coolant systems are required. In view of these fears, the opening of new nuclear power plants in Tamil Nadu and Haryana are being opposed by the residents of the concerned areas.