What Is Radium Definition Atomic Number Properties Isotopes and Uses
Ra Element
Radium is a type of chemical element that has the symbol Ra and an atomic number of 88. It is the sixth element in the group 2 of the periodic table, also called the alkaline earth metals. Pure radium is silvery-white in colour, however, it readily reacts with nitrogen rather than oxygen when exposed to air, and forms a black surface layer of radium nitride. All of the isotopes of radium are highly radioactive and the most stable isotope is radium-226 that has a half-life of 1600 years and decays into radon gas (specifically the isotope called radon-222). When the element radium decays, it yields ionizing radiation as a product that can excite the fluorescent chemicals and cause radioluminescence. In this article, we will learn about radium, the Ra element in detail, the use of radium, radium properties, the radium electronic configuration, and the effects of radium.
What is Radium?
Radium is a type of chemical element with a symbol Ra. It is the sixth element that lies in the group 2 of the periodic table. Pure form of radium is silvery-white in colour, however, it combines with nitrogen readily when it is exposed to air and forms a black surface layer of the radium nitride. Radium was discovered in the year 1898 by Marie Sklodowska Curie and Perre Curie in the form of radium chloride. They had extracted the radium compound from the element called uraninite. It is found in the uranium ores at the concentration of 1 part per 3 million parts uranium.
Physical Properties of Radium
Let us now look at the physical properties of radium.
Radium is known to be the heaviest known alkaline earth metal and is the one and only radioactive member of its periodic group. Its physical and chemical properties are much closely similar to its lighter congener which is barium.
Radium is a highly reactive metal to be known and it always exhibits its group oxidation state. It has the tendency to form the colourless Ra²⁺ cation in aqueous solution, which is highly basic in nature and does not form any complexes. Most of the radium compounds are for this reason simple ionic compounds.
Radium emits the alpha rays, beta rays, and gamma rays when it is mixed with the beryllium produces neutrons.
Let us now take a look at some of the chemical properties of radium.
Chemical Properties of Radium
Radium Uses
Let us now take a look at what can radium be used for and see some of its applications.
Some of the practical uses of radium are due to its radioactive properties. Radium was previously used in the self-luminous paints for watches, aircraft switches, nuclear panels clocks, and instrument dials.
Ra was earlier used as an additive in the products like hair cream, toothpaste, and even food items.
Radium was also used in the field of medicine for producing radon gas that in turn was used as a cancer treatment.
Health Effects of Radium
Now that you know about radium, let us see how radium is harmful to the health of the humans.
Radium is highly radiotoxic and carcinogen when it is inhaled, ingested or exposed and when it is used in the treatment of cancer and several other body disorders. The Ra element is more than a million times more radioactive than the same mass as that of uranium.
FAQs on Radium Element in Chemistry Properties Isotopes and Applications
1. What is radium in chemistry?
Radium is a radioactive alkaline earth metal with atomic number 88 and symbol Ra.
- It belongs to Group 2 of the periodic table.
- It was discovered in 1898 by Marie Curie and Pierre Curie.
- Radium is highly radioactive and emits alpha particles during decay.
- It commonly forms the ion Ra2+ in compounds.
2. What is the electron configuration of radium?
The electron configuration of radium (Ra) is [Rn] 7s2.
- Radium has 88 electrons.
- It follows the noble gas core of radon (Rn).
- The two electrons in the 7s orbital explain why radium forms Ra2+ ions.
3. What type of element is radium?
Radium is a Group 2 alkaline earth metal and a highly radioactive element.
- It is located in period 7 of the periodic table.
- It shows metallic properties such as conductivity and reactivity.
- Like other alkaline earth metals, it forms ionic compounds with a +2 oxidation state.
4. What is the most common oxidation state of radium?
The most common oxidation state of radium is +2.
- Radium loses two 7s electrons to form Ra2+.
- This behavior is similar to other alkaline earth metals such as Ba2+ and Ca2+.
- Compounds like RaCl2 and RaSO4 contain radium in the +2 state.
5. Why is radium radioactive?
Radium is radioactive because its nucleus is unstable and undergoes nuclear decay to achieve stability.
- The most stable isotope, Ra-226, emits alpha particles.
- An example decay equation is: 226Ra → 222Rn + 4He.
- This process converts radium into radon-222, a noble gas.
6. What is the atomic mass of radium?
The atomic mass of radium is approximately 226 u, based on its most stable isotope Ra-226.
- Radium has no stable isotopes.
- Ra-226 has a half-life of about 1600 years.
- Because it is radioactive, its atomic mass reflects the mass number of its longest-lived isotope.
7. How does radium react with water?
Radium reacts with water to form radium hydroxide and hydrogen gas.
- The balanced chemical equation is: Ra(s) + 2H2O(l) → Ra(OH)2(aq) + H2(g).
- This reaction is similar to other Group 2 metals but more vigorous due to increased reactivity down the group.
- The product Ra(OH)2 is a strong base.
8. What are common compounds of radium?
Common radium compounds include radium chloride (RaCl2), radium sulfate (RaSO4), and radium hydroxide (Ra(OH)2).
- Radium chloride is an ionic salt formed with chloride ions.
- Radium sulfate is sparingly soluble, similar to BaSO4.
- These compounds contain the Ra2+ ion.
9. What is the half-life of radium-226?
The half-life of radium-226 is approximately 1600 years.
- Half-life is the time required for half of a radioactive sample to decay.
- Ra-226 decays by alpha emission to form radon-222.
- This long half-life contributes to its persistent radioactivity in the environment.
10. How is radium different from barium?
Radium differs from barium mainly in its radioactivity and higher atomic number.
- Radium (Z = 88) is highly radioactive, while barium (Z = 56) is stable.
- Radium has a larger atomic radius and greater density.
- Both form +2 oxidation state ions and similar compounds like RaSO4 and BaSO4.
