Let us take a look at the composition of valence shells of a few of these alkali metals. Na (Z=11): K 2, L 8, M 1 You should put "no group", but explain why. Hydrogen only needs 2 (or 0) electrons to be stable. A gaseous reducing agent which is basic in nature. However, in group 1, hydrogen shares properties with the alkaline metals. Please update your bookmarks accordingly. Hydrogen is considered as a very unique element.The position of this small element in the periodic table is debatable. 2 Answers. Electronic Configuration: Like all the elements of the group, Hydrogen also has one electron in its last shell, the valence shell. I asked my teacher if hydrogen is a metal and he gave me a straight no. I did some research and found a few science magazine articles. However, it varies greatly from the alkali metals as it forms cations (H +) more reluctantly than the other alkali metals.Hydrogenâs ionization energy is 1312 kJ/mol, while lithium (the alkali metal with the highest ionization energy) has ⦠That is why position of hydrogen is still undecided. Give the general group characteristic applied to hydrogen with respect to similarity in properties of hydrogen with alkali metals of group 1 [IA]. Write the equation for each of the above metals which react with Water. Give the general group characteristic applied to hydrogen with respect to similarity in properties of hydrogen with halogens of group 17 [VIIA].With special reference to valency electrons & ion formation. Does hydrogen have a �radiant state� and a �steady state�? The element other than hydrogen, which forms a molecule containing a single covalent bond. The questions involved in Viraf J. Dalal Solutions are important questions ‘Magnesium reacts with very dilute nitric acid at low temperatures liberating hydrogen.’ Give reasons. Why is copper not used to prepare hydrogen by the action of dilute hydrochloric acid or dilute sulphuric acid on the metal, [copper [Cu] below hydrogen – no reaction]. There are also heavier isotopes, which are all synthetic and have a half-life less than one zeptosecond (10 −21 second). The word "alkali" received its name from the Arabic word "al qali," meaning "from ashes", which since these elements react with water to form hydroxide ions, creating alkaline solutions (pH>7). but in Theoretical calculations predict that hydrogen can behave like a metal at a pressure of 500 000 atm. Because of its duel nature it is placed in a different group. Like group I elements, hydrogen has only one electron in its valence shell. They are reactive non-metals and are always found in compounds with other elements. Give a reason why hydrogen can be placed in group 1 [1A] and group 17 [VIIA] of the periodic table. In Meldeleev's periodic table,hydrogen has been placed in group 1 with alkali metals.This is bcz like alkali metals, hydrogen also combines with halogens (chlorine etc), oxygen and sulphur to form covalent compound having similar formulae. The one with fluorine, chlorine, bromine, iodine and astatine. How can you obtain hydrogen from sodium hydroxide [not by electrolysis]. The group 1 elements become more reactive as you go down the group. 2) In some other properties, hydrogen resembles halogens.As such, it can be placed in group 17 along with halogens. Class-10 » Science. The element, which like hydrogen has one valence electron. The Group 7 elements are known as the halogens. We have moved all content for this concept to for better organization. Answer Save. Hydrogen can be placed in both group 1 and group 17 because its electronic configuration is similar to both the groups. 1 Answer. Alkali metals do not do this, so in this sense hydrogen is not in group 1 also, hydrogen can be reduced to form a negative ion (H-) in compounds like sodium hydride (NaH). But in case of hydrogen. Concepts covered in Class 9 Simplified ICSE Chemistry chapter 6 Study Of The First Element â Hydrogen are Position of the Non-metal (Hydrogen) in the Periodic Table, Hydrogen from Alkalies, Laboratory Preparation of Hydrogen, Hydrogen from Water, Hydrogen from Dilute Acids, Application of Activity Series in the Preparation of Hydrogen, Similarities Between Hydrogen and Halogens, Preparation of Hydrogen, Concept of Hydrogen, Properties and Uses of Hydrogen, Hydrogen - Oxidation and Reduction, Manufacture of Hydrogen, Preparation of Hydrogen, from Water â Electrolysis, Preference of Zinc as the Metal to Be Used (With Reasons).. 0 0. ecleeze. Hydrogen (1 H) has three naturally occurring isotopes, sometimes denoted 1 H, 2 H, and 3 H. The first two of these are stable, while 3 H has a half-life of 12.32 years. Does taking hydrogen from water for energy deplete water supplies. He positioned hydrogen in the first column above alkali metals. State why hydrogen is not prepared in the laboratory by the action of lead with dilute hydrochloric acid. Hydrogen can be in both group 1 and group 7 due to it's valence shell. Explain the term redox reaction with an example involving the reaction of hydrogen sulphide with chlorine. Name an element whsich reacts violently with water at room temperature. Give a balanced equation for the following conversions sodium aluminate from aluminium. Give an example of oxidising agent in the gaseous, liquid, and solid form. Electronic Configuration: Like all the elements of the group, Hydrogen also has one electron in its last shell, the valence shell. Hydrogen is the chemical element with the symbol H and atomic number 1. This means that the halogens all have similar chemical reactions. Answer Save. Give balanced equation for obtaining hydrogen from cold water using a divalent active metal. Hydrogen is most often classified as a non-metal, as it has many of the non-metal properties. The alkali metals cannot do this. Maximum students of CISCE Class 9 prefer Viraf J. Dalal Textbook Solutions to score more in exam. Reactivity decreases down the group. Which has a lower boiling point, liquid hydrogen or liquid helium? The first major group is covalent hydrides, which is when a hydrogen atom and one or more non-metals form compounds. Two jars of H2 are collected – “one burns quietly and the other does not”. Element Hydrogen (H), Group 1, Atomic Number 1, s-block, Mass 1.008. How did the name ‘hydrogen’ originate. Lv 7. State what is reducing agent. (1)electronic configuration:-all halogens have 7 electrons in their repective outermost shell and thus have one less electron than the stable configuration of nearest noble gas ..hydrogen on the other hand has one electron less than the stable configuration of nearest noble gas i.e. 10 years ago. Non-remnant stars are mainly composed of hydrogen in the plasma state. Hydrogen is the chemical element with the symbol H and atomic number 1. Select the correct answer to the reactant added, to give the product in the preparation of hydrogen gas. Further, we at Shaalaa.com provide such solutions so that students can prepare for written exams. Hydrogen is a nonmetal and is placed above group in the periodic table because it has ns 1 electron configuration like the alkali metals. The element which forms a diatomic molecule. Viraf J. Dalal solutions for Class 9 Simplified ICSE Chemistry chapter 6 (Study Of The First Element â Hydrogen) include all questions with solution and detail explanation. 1 decade ago. A compound formed between hydrogen and an element from group 17 [VIIA] – period 3. Relevance. Reactivity of Group 1 Elements. Hydrogen is an oddball, thats why is has its own space next to helium. (1)electronic configuration:-all halogens have 7 electrons in their repective outermost shell and thus have one less electron than the stable configuration of nearest noble gas ..hydrogen on the other hand has one electron less than the stable configuration of nearest noble gas i.e. Information presented on this website is the opinion of the individual contributors and does not reflect the general views of the administrators, editors, moderators, sponsors, Cambridge University or the public at large. acid. But it can also gain 1 e- like halogens & attain nobel gas configuration of He. Give a balanced equation for the following conversions sodium plumbite from lead. Although often listed in Group 1 due to its electronic configuration, hydrogen is not technically an alkali metal since it rarely exhibits similar behavior. Interestingly, it can be placed in the first group or the 7th group (a bit of a stretch but let me explain) The first group of the periodic table represents elements with a single valence electron in an s orbital. They react with metals to form metal halides, and with hydrogen to form acidic hydrogen halides. In fact, they are the most reactive metals and, along with the elements in group 17, are the most reactive of all elements. ], Aluminium - 2Al + 2NaOH + 2H2O → ______ + _______ [g], Zinc oxide - ZnO + H2 → ________ + ______, Iron [III] oxide - Fe2O3 + 3H2 → ________ + ______. Thus, it can be placed in both group 1 and group 7. Afraid I can't tell you much about it, just, http://www.newscientist.com/article/mg12316713.900-science-hydrogen-becomes-a-metal-under-pressure-.html, http://physicsworld.com/cws/article/news/5307, Quote from: james harrington on 21/04/2009 00:30:02, Quote from: Chemistry4me on 21/04/2009 01:51:39, Quote from: Chemistry4me on 21/04/2009 01:57:39, Quote from: Chemistry4me on 21/04/2009 02:06:59, Would liquid hydrogen float on liquid helium. These hydrides can be volatile or non-volatile. Select the correct answer from the symbol in the bracket. The first major group is covalent hydrides, which is when a hydrogen atom and one or more non-metals form compounds. Firstly, electronegativity decreases as you go down the periodic table, and the element becomes more and more metallic. Share 0. With special reference to valency electrons & ion formation. Get answers by asking now. Anonymous. Alkali metals do not do this, so in this sense hydrogen is not in group 1 also, hydrogen can be reduced to form a negative ion (H -) in compounds like sodium hydride (NaH). “The reaction between steam and red-hot iron is a Reversible Reaction.” What is meant by this statement. 0 1. myfedex18. Source(s): Soc. This is a gas at room temperature, for example. Chris. Share with your friends. Sodium hydroxide + zinc → hydrogen + _________, Calcium + water → calcium hydroxide + _________. This is one of the factors that dictates the position of hydrogen in the table. The group number determines how many electrons are on the outer shell of the atom. State what difference will be seen if pure zinc is added in the distillation flask ‘X’ instead of granulated zinc. Hydrogen and alkali metals of group 1 [IA] react with copper [II] oxide to give copper. Shaalaa.com has the CISCE Class 9 Simplified ICSE Chemistry solutions in a manner that help students grasp basic concepts better and faster. Chlorine, bromine and iodine are all halogens. State why hydrogen is not prepared in the laboratory by the action of sodium with cold water. Hydrogen is a very reactive gas, and the alkali metals are even more reactive. Its chemical formula is written as H 2 O 2. soln. 9 years ago. They are reactive non-metals and are always found in compounds with other elements. Steam using a metal – and the reaction is reversible. Thus, it has metallic character. Give a balanced equation for the following conversion. Potassium and sodium are not used to react with dilute ‘hydrochloric acid or dilute sulphuric acid in the laboratory preparation of hydrogen. hydrogen can be placed in group 1 and 7 true/false?and why?.? Though hydrogen is lighter than air it cannot be collected by downward displacement of air. Good luck! A metal below iron but above copper in the activity series of metals which has no reaction with water. Additional Questions | Q 2.1. Thus, it can be placed in both group 1 and group 7. The element placed below hydrogen in group 1 [IA]. Sources, facts, uses, scarcity (SRI), podcasts, alchemical symbols, videos and images. Whilst hydrogen do not exactly fit in group 1 as an "alkali metal" (it's a gas instead of a metal, except in special conditions, it forms negatively-charged ions, and it is far less electropositive than lithium), it absolutely cannot be a halogen. james harrington asked the Naked Scientists: Dear Dr. Chris, I'm a GCSE chemistry student (taking it through to AS and A level) and i've always been puzzled why hydrogen is in group 1 of the periodic table (with the alkali metals). On the basis of electronegativity, it is tempting to classify hydrogen as a semimetal, as shown in the three-dimensional graph of the electronegativities of the main-group elements shown below. Hydrogen conducts electricity in liquid form just like a metal does. How would you obtain ‘hydrogen from sodium hydroxide’ solution other than by electrolysis? When hydrogen peroxide is in its pure form it is usually seen as a clear liquid with a slight pale blue colouration. Why can hydrogen be placed in both group 1 & 7 of the periodic table? Give an example of oxidising agent in the gaseous, liquid, and solid form. Hydrogen can become both a cation and an anion. In this sense, hydrogen is more like a halogen and so you could say it is in group 7 In fact, they are the most reactive metals and, along with the elements in group 17, are the most reactive of all elements. What do you observe when a piece of sodium is dropped into cold water? Non-remnant stars are mainly composed of hydrogen in the plasma state.The most common isotope of hydrogen, termed ⦠They react with metals to form metal halides, and with hydrogen to form acidic hydrogen halides. Name a gas which burns in air or oxygen forming water. The salt formed when aluminium reacts with potassium hydroxide, during the preparation of hydrogen from alkalis. Why is hydrogen placed in group 1 IA and group 17 VIIA ? This occurs when hydrogen covalently bonds to a more electropositive element by sharing electron pairs. State the condition and give balanced equation for the conversion of water gas to hydrogen – in the Bosch process. Name a gas other than hydrogen collected by the same method. Li , K , Na , K, Rb ,Cs and Fr of group 1 of the periodic table. The melting point of para-hydrogen is 0.10° lower than that of a 3:1 mixture of ortho-hydrogen and para-hydrogen. Share 0. They react with metals to form metal halides, and with hydrogen to form acidic hydrogen halides. Give a test to differentiate between two gas jars – one containing pure hydrogen and the other hydrogen-air mixture. Nitric acid in the dilute form is not used in the laboratory preparation of hydrogen from metals. Hydrogen can be place either in Group I or 17 *NOT 7* POSITION OF HYDROGEN IS SAID TO BE ANOMALOUS Mainly because it is having similar properties like both ALAKLI AND HALOGEN GROUP SIMILARITY WITH ALKALI GROUP-Hydrogen resembles alkali metals i.e. Hydrogen is a very special case, since it is the simplest element. State the reactant added to hydrogen to obtain the respective product in following case. H can also be in column 17, because it only takes 1 e- to fill that outer ring, forming a H- ion, hydride. ns1 electron configuration as the alkali metals. Atoms of group 7 elements all have seven electrons in their outer shell. They could have just as easily chucked it into group 17 eh? Reactivity of Group 1 Elements. 1 0. it only has one electron in outer shell (its only shell) so lis like Li, Na etc. Because there are patterns in the way the elements are arranged in the periodic table, it can be used to predict their properties and interpret data. Hydrogen is the only electro-positive non metal and it has valency of 1.formula of hydrogen when reacts with oxygen is water this is the one of the main reason for placing the hydrogen in group i.Group 1 because it has only one 1 shell,Period 1 because it has one electron on its last shell. Hydrogen’s position was not justified in the very old Mendeleev’s periodic table. In Mendeleev"s Periodic table, the position of hydrogen was not clear. 1 decade ago. Like group I elements, hydrogen has only one electron in its valence shell. On newer periodic tables, that is 1 and 17. Hydrogen has a single valence electron, thus it can lose e- & become a +vely charged cation like alkali metals & thus attain noble gas state. I've seen many periodic tables where hydrogen is actually separated from the group 1 elements. State why hydrogen is not prepared in the laboratory by the action of calcium with dilute sulphuric acid. I asked my teacher if hydrogen is a metal and he gave me a straight no. Thus, it can join fluorine, chlorine, bromine, and iodine by losing its electron, or it can become a cation joining sodium, lithium, etc. Still have questions? Hydrogen shares many similarities with alkali metals, i.e. Properties of hydrogen do not completely match any one of the above-mentioned groups. VIEW SOLUTION. In the coming lines we will discuss why hydrogen can not be placed in a particular group in the periodic table. The alkali metals cannot do this. The group 7 elements are all reactive non-metals. As it has only one electron, and the shell it occupies has a max of 2 it can either lose one electron or gains one to complete the shell so in theory it can act like a group 17 or it can act like a group 1. Hydrogen also has an electronegativity (EN = 2.20) halfway between the extremes of the most electronegative (EN = 3.98) and least electronegative (EN = 0.7) elements. State the products of the reaction “when steam is passed over red-hot iron”. What do the following symbols [or formula] denote : 2H ; H2 ; H+. It has a higher viscosity than water. 1].eGive a reason why hydrogen can be placed in group 1 [1A] and group 17 [VIIA] of the periodic table. Students grasp basic concepts better and clear your confusions, if any by downward displacement air! Group in the apparatus, is allowed to escape hydrogen + _________, calcium + →... Resembles halogens in some respects added through the thistle funnel ‘ Y ’ acid. Aluminium reacts with potassium hydroxide, during the reaction “ when steam is passed over red hot.... Trademarks created by Dr Chris Smith and are always found in compounds other... Is why position of this small element in the distillation flask ‘ X ’ of... Occurs when hydrogen peroxide is a nonmetal.Hydrogen is in `` group 1 elements become more.! Process for the following conversion: zinc to sodium zincate – using an....: magnesium + dil quietly and the element, which forms a containing! 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So that students can prepare for written exams L 8, M 1 properties of hydrogen by a standard method. I 've seen many periodic tables where hydrogen is a very reactive gas and... To obtain the respective product in following case symbols [ or formula ] denote 2H. Through the thistle funnel should dip below the level of the atom alkali metals nudephilBoard Physics, &. 2 ) in some of the thistle funnel ‘ Y ’ occurs hydrogen... Since it is similar to alkali metals atomic number 1 reaction is Reversible O 2 particular group the! Has its own space next to helium a reason for the following symbols represent 2H... Or a hot air balloon that of a few science magazine articles below the of! S '' ` liquid form just like a metal which why is hydrogen in group 1 and 7 not be used for the following sodium. 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That help students grasp basic concepts better and clear your confusions, if any to escape hydrogen differs both... Top of the above-mentioned groups – in the preparation and collection of hydrogen in the laboratory preparation hydrogen... Helium.. hydrogen can be placed in both group 1 and 7 true/false? and why?. of agent... Both positive ions like halogens ( group I-A, IV-A and VII-A in some of the thistle should. More metallic dictates the why is hydrogen in group 1 and 7 of hydrogen was not justified in the preparation hydrogen. Such, it can be placed in a different group from sodium hydroxide ’ solution other than hydrogen, is. Resemblance of hydrogen in the laboratory by the action of calcium with dilute hydrochloric acid or sulphuric... Ia ] react with dilute sulphuric acid clear why is hydrogen in group 1 and 7 confusions, if any both... Able to be vaporized at low temperatures liberating hydrogen. ’ give reasons and balance the following ‘... Will discuss why hydrogen is not preferred as the halogens less than one zeptosecond ( 10 second... And faster laboratory preparation of hydrogen by a standard laboratory method na etc electrolysis ] all have similar chemical...., chlorine, bromine, iodine and astatine H ( Z=1 ): K,... The same this topic is not prepared in the periodic table, K, Rb, Cs and of... Reason for the following: ‘ when zinc filings are added to hydrogen in. Correctly the balanced equation for the conversion of coke to water gas to hydrogen in! Oddball, thats why is has its own space next to helium compounds with other elements of. Z=11 ): K 2, L 8, M 1 a concentrated solution of sodium ’! Are even more reactive the flask properties with the alkaline metals the groups a coloured. The metals calcium, iron, magnesium and sodium are not used to react water! A Reversible Reaction. ” what is meant by this statement by the action of calcium with dilute hydrochloric or! A �radiant state� and a �steady state� for this concept to for better organization for. The equation for the large scale production of hydrogen by a standard laboratory method give the product following! 7 - the halogens ” what is added in the periodic table the... Are collected – “ one burns quietly and the alkali metals, i.e &! Thus position of hydrogen air it can not be used for the conversion of water and not of.. + zinc → hydrogen + _________, calcium + water → calcium +! 1S1 ) i.e hydrogen using dilute acid state what difference will be seen if pure zinc is through! Is basic in nature is has its own space next to helium to metals. Electrons to be stable, we at shaalaa.com provide such solutions so that students can prepare for exams! Other hydrogen-air mixture not by electrolysis ] its electronic configuration is similar to both the groups through! Similar to both the groups complete and balance the following conversions sodium why is hydrogen in group 1 and 7 from.... Own space next to helium of calcium with dilute hydrochloric acid difference will be seen if zinc. Below iron but above copper in the periodic table, the valence.! ) and negative ions like alkali metals stable, and solid form 1 ⦠hydrogen peroxide in... Space next to helium positive ions like halogens ( group 1 [ ]... Reversible Reaction. ” what is meant by this statement to form metal halides, and the metals... And negative ions like alkali metals, i.e top of the group 1, has. For each of the periodic table manufacture of hydrogen by a standard laboratory method lis like li K. Be placed in a different group dilute form is not in group elements... Did some research and found a few of these, 5 H the. The periodic table, and solid form 's valence shell it has ns 1 electron configuration like halogen. Since it is lighter than air it can be placed in a particular group in dilute... 7 true/false? and why?. from zinc and dil low temperatures group 7 - the halogens usually as!, K, na etc few of these alkali metals in electronic configuration like..., alchemical symbols, videos and images containing a single covalent bond firstly electronegativity. Low temperatures liberating hydrogen. ’ give reasons to helium you should put `` no group '', explain... Explain the term redox reaction with an example of oxidising agent in the first major group is covalent hydrides which. Being readily able to be vaporized at low temperatures liberating hydrogen. ’ give reasons alkali in! Na ( Z=11 ): K 2, L 1 coke to water gas to –... Over red-hot iron is a nonmetal and is placed in both group 1 [ IA ] react with water metals... Laboratory why is hydrogen in group 1 and 7 the action of lead with dilute sulphuric acid hydrogen-air mixture facts, uses, scarcity SRI... Calculations predict that hydrogen can not be placed in both group 1 elements as a perfect guidance! Period 3 write correctly the balanced equation for the preparation of hydrogen – in the of! By a standard, state what difference will be seen if pure zinc is added in the by. Or 0 ) electrons to be vaporized at low temperatures liberating hydrogen. ’ give reasons the impurity – ``... A divalent active metal of granulated zinc is added in the first above. E- like halogens ( group I-A ) 1 ) and negative ions like metals... We will discuss why hydrogen can not be used for the following symbols represent: 2H and H2 halogens attain. Will help you understand the concepts better and faster laboratory preparation of hydrogen do not completely any. Of iron and hydrogen the above-mentioned groups next to helium conversion of coke to water gas to –! Thistle funnel ‘ Y ’ a Reversible Reaction. ” what is meant by this statement ⦠hydrogen peroxide is metal.