31 Jan Group VII Elements in Periodic Table
Chemistry tuition classes in Miracle Learning Centre is easy to understand and help you in the chemistry tuition application questions. If you do not understand chemistry in school, you must definitely come for chemistry tuition classes at Miracle Learning Centre. Let us learn about Group VII elements in periodic table in this chemistry tuition lesson.
Group VII non metals in periodic table are called halogens. Group VII halogens include fluorine, chlorine, bromine, iodine and astatine. There is a trend for these elements going down the group, hence it is useful to know the trend and we can predict the properties of the elements below. Fluorine is pale green gas. Chlorine is a yellowish green gas. Bromine is a reddish brown liquid. Iodine is a black solid. Hence we can tell the color darkens down the group. The melting point and boiling point of Group VII elements increases down the group. The trend changes from gaseous to liquid to solid state down the group. Hence we can predict that astatine will be a black solid. Group VII elements form ionic compounds with metals, especially with group I and II metals. For example, sodium chloride has a giant ionic lattice structure and can withstand high temperature. Group VII elements have a melting point and boiling point which increases down the group. As we move down the group, the strength of the intermolecular force increases, hence more energy is needed to break these intermolecular forces of attraction, hence melting point and boiling point increases.
The reactivity of halogens in group VII decreases down the group. The most reactive halogen is fluorine. It gets more difficult to gain an electron down the group as the size of the atom increases. The most reactive non-metal is fluorine. This is followed by chlorine, bromine and iodine.
The student at Miracle Learning Centre asked, “Why is it important to learn about group VII elements?” Mrs Lew, chemistry teacher at Miracle Learning Centre replied, “By learning about group VII elements, we can identify how each element can be put to good use. For example chlorine is used to sterilise water. Group VII elements are also used as oxidising agents, to oxidise iron from iron(II) compounds to iron(III) compounds. Displacement reactions involving halogens help us to identify which halogen is more reactive. Chlorine reacts with potassium iodide to form potassium chloride and iodine. This is because chlorine is more reactive than iodine and chlorine can displace iodide ions from its solution. The colourless solution brown. On the other hand, iodine cannot react with potassium chloride. This is because iodine is less reactive than chlorine and iodine cannot displace chloride ions from its solution. ”
Displacement reactions also occurs in metals. Displacement reactions involving metals help us to identify which metal is more reactive. Zinc reacts with copper(II) nitrate to form zinc nitrate and copper metal. This is because zinc is more reactive than copper and can displace copper(II) ions from its solution. The blue solution turns colourless and a brown solid of copper is formed. On the other hand, copper cannot react with zinc nitrate.
Miracle Learning Centre aims to educate students about group VII elements. Do come to Miracle Learning Centre for more chemistry tuition lessons to learn more about group VII elements in the Periodic Table. Chemistry tuition teachers give clear and concise explanations that you can understand easily. Other than Group VII elements, we teach the other chemistry tuition topics like electrolysis, metals, redox reactions and organic chemistry as well.
At Miracle Learning Centre, you will not just learn Chemistry, but you will feel motivated, energized, and excited about the subject. At our fun filled classes of A level chemistry tuition, O level chemistry tuition, JC chemistry tuition, teachers will teach you with new and advanced methods and will never make the lessons sound boring.