2K CrO H SO K CrO K SO H O potassium dichromate yellow. orange
|
|
- Erika Gallagher
- 5 years ago
- Views:
Transcription
1 Potassium dichromate, (KCrO7) Potassium dichromate is one of the most important compound of chromium, and also among dichromates. In this compound Cr is in the hexavalent (+6) state. Preparation : It can be prepared by any of the following methods, (i) From potassium chromate : Potassium dichromate can be obtained by adding a calculated amount of sulphuric acid to a saturated solution of potassium chromate. K CrO H SO K CrO K SO H O potassium dichromate yellow orange potassium chromate KCrO7 Crystals can be obtained by concentrating the solution and crystallisation. (ii) Manufacture from chromite ore : KCrO7 is generally manufactured from chromite ore (FeCrO4). The process involves the following steps. (a) Preparation of sodium chromate. Finely powdered chromite ore is mixed with soda ash and quicklime. The mixture is then roasted in a reverberatory furnace in the presence of air. Yellow mass due to the formation of sodium chromate is obtained. 4FeCrO 4 O FeO3 4CrO 3 4CrO 3 8NaCO3 6O 8NaCrO4 8CO (g) 4FeCr O 8Na CO 7O Fe O 8CO g 8Na CrO sodium chromate Page1
2 The yellow mass is extracted with water, and filtered. The filtrate contains sodium chromate. The reaction may also be carried out by using NaOH instead of NaCO3.The reaction in that case is, 4FeCrO 4 16NaOH 7O 8NaCrO4 FeO3 8HO (b) Conversion of chromate into dichromate. Sodium chromate solution obtained in step (a) is treated with concentrated sulphuric acid when it is converted into sodium dichromate. Na CrO H SO Na Cr O Na SO H O sodium chromate sodium dichromate On concentration, the less soluble sodium sulphate, NaSO4.10HO crystallizes out. This is filtered hot and allowed to cool when sodium dichromate, NaCrO7.HO, separates out on standing. (c) Concentration of sodium dichromate to potassium dichromate. Hot concentrated solution of sodium dichromate is treated with a calculated amount of potassium chloride. When potassium dichromate being less soluble crystallizes out on cooling. Na CrO KCl K Cr O NaCl 7 7 sod.dichromate pot.dichromate Physical properties (i) Potassium dichromate forms orange-red coloured crystals. (ii) It melts at 699 K. (iii) It is very stable in air (near room temperature) and is generally, used as a primary standard in the volumetric analysis. Page
3 (iv)it is soluble in water though the solubility is limited. Chemical properties (i) Action of heat : Potassium dichromate when heated strongly. decomposes to give oxygen. (ii) Action of acids 4K Cr O s 4K CrO (s) Cr O (s) 3O (a) In cold, with concentrated HSO4, red crystals of chromium trioxide separate out. K Cr O (aq) conc.h SO KHSO (aq) CrO s H O On heating a dichromate-sulphuric acid mixture, oxygen gas is given out. KCrO 7 8HSO4 KSO4 Cr (SO 4 ) 3 8HO 3O (b) With HCl, on heating chromic chloride is formed and Cl is liberated. K Cr O 14HCl aq CrCl KCl aq 7H O 3Cl g 7 aq 3 aq (iii) Action of alkalies : With alkalies, it gives chromates. For example, with KOH, K Cr O KOH K CrO H O 4 4 orange yellow On acidifying, the colour again changes to orange-red owing to the formation of dichromate. KCrO4 HSO4 KCrO 7 KSO4 HO Actually, in dichromate solution, the CrO 7 ions are in equilibrium with CrO 4 ions. Cr O 7 H O CrO H 4 Page3
4 (iv) Oxidising nature : In neutral or in acidic solution, potassium dichromate acts as an excellent oxidising agent, and CrO 7 gets reduced to Cr 3+. The standard electrode potential for the reaction, Cr O 14H 6e Cr 7H O is V. This indicates that 3 7 dichromate ion is a fairly strong oxidising agent, especially in strongly acidic solutions. That is why potassium dichromate is widely used as an oxidising agent, for quantitative estimation of the reducing agents such as, Fe +. It oxidises, (a) Ferrous salts to ferric salts K CrO 4H SO K SO Cr SO 4H O 3 O FeSO H SO O Fe SO H O K Cr O 6FeSO 7H SO K SO Cr SO 3Fe SO 7H O Ionic equation: Cr O 14H 6Fe Cr 6Fe 7H O 7 (b) Sulphites to sulphates and arsenites to arsenates. K Cr O 4H SO K SO Cr SO 4H O 3 O NaSO 3 [O] NaSO 4 ] 3 K Cr O 4H SO 3Na SO K SO Cr SO 3Na SO 4H O Ionic equation: Cr O 8H 3SO Cr 3SO 4H O Similarly, arsenites are oxidised to arsenates. Cr O 8H 3AsO Cr 3AsO 4H O (c) Hydrogen halides to halogens. K Cr O 4H SO K SO Cr SO 4H O 3 O HX O HO X ] 3 Page4
5 K Cr O 4H SO 6HX K SO Cr SO 7H O 3X where, X may be Cl, Br, I. 3 Ionic equation : Cr O 8H 6HX Cr 3X 7H O (d) Iodides to iodine 7 K Cr O H SO K SO Cr SO 4H O 3 O KI HO O KOH I ] 3 KOH HSO4 KSO4 HO] 3 K Cr O 7H SO 6KI 4K SO Cr SO 3I 7H O Ionic equation : Cr O 14H 6I Cr 7H O 3I 7 Thus, when KI is added to an acidified solution of KCrO7 iodine gets liberated. (e) It oxidises HS to S. KCrO 7 4HSO4 KSO4 Cr (SO 4 ) 3 4HO 3 O HS O HO S] 3 K Cr O 4H SO 3H S K SO Cr SO 7H O 3S Ionic equation : Cr O 8H 3H S Cr 3S 7H O 7 (v) Formation of insoluble chromates : With soluble salts of lead, barium etc., potassium dichromate gives insoluble chromates. Lead chromate is an important yellow pigment. Pb NO K Cr O H O PbCrO KNO HNO Page5
6 (vi) Chromyl chloride test : When potassium dichromate is heated with conc. HSO4 in the presence of a soluble chloride salt, the orange-red vapours of chromyl chloride (CrOCl) are formed. K Cr O 4NaCl 6H SO KHSO 4NaHSO CrO Cl heat chromyl chloride orangered vapours Chromyl chloride vapours when passed through water give yellowcoloured solution containing chromic acid. CrO Cl H O HCl H CrO 4 Chromic acid. ( yellow solution) Chromyl chloride test can be used for the detection of chloride ion is any mixture. Uses : Potassium dichromate is used as, (i) (ii) An oxidising agent In chrome tanning (iii) The raw meterial for preparing large number of chromium compounds (iv) Primary standard in the volumetric analysis. Structures of Chromate and Dichromate Ions Chromates and dichromates are the salts of chromic acid (HCrO4). In solution, these ions exist in equilibrium with each other. Chromate ion has four oxygen atoms arranged tetrahedrally around Cr atom. (see Fig). Dichromate ion involves a Cr O Cr bond as shown in Fig. Page6
T 619 cm-84 TENTATIVE STANDARD 1933 OFFICIAL STANDARD 1935 CORRECTED 1944 CORRECTED 1953 CLASSICAL METHOD TAPPI. Analysis of salt cake
T 619 cm-8 TENTATIVE STANDARD 19 OFFICIAL STANDARD 195 CORRECTED 19 CORRECTED 195 CLASSICAL METHOD 198 198 TAPPI The information and data contained in this document were prepared by a technical committee
More informationWhat is: (a) aqua fortis, (b) aqua regia (c) Fixation of Nitrogen?
EXERCISE.1 Question 1: What is: (a) aqua fortis, (b) aqua regia (c) Fixation of Nitrogen? Solution 1: Book Name: Selina concise (a) Aqua fortis: Nitric acid is called aqua fortis. Aqua fortis means strong
More informationSome Basic Concepts of Chemistry
Q 1. Some Basic Concepts of Chemistry What weight of AgCI will be precipitated when a solution containing 4.77 g of NaCI is added to a solution of 5.77 g of AgNO 3? (IIT JEE 1978 3 Marks) Q 2. One gram
More informationChemistry. TOPIC : Redox Reactions. products are PH3 and NaH2PO2. This reaction is an examplee of. (b) Reduction (d) Neutralization
TOPIC : Redox Reactions Date : Marks : 1 mks Time : ½ hr 1. When P reacts with caustic soda, the products are PH and NaHPO. This reaction is an examplee of (a) Oxidation (c) Oxidation and reduction (redox)
More informationKULLEĠĠ SAN BENEDITTU Boys Secondary, Kirkop
KULLEĠĠ SAN BENEDITTU Boys Secondary, Kirkop Mark HALF-YEARLY EXAMINATION 2013/2014 Junior Lyceum Programme FORM 4 CHEMISTRY TIME: 1h 30min Question 1 2 3 4 5 6 7 Global Mark Max. Mark 10 16 15 11 8 20
More informationICSE-Science 2 (Chemistry) 2004
ICSE-Science 2 (Chemistry) 2004 Answers to this Paper must be written on the paper provided separately. You will not be allowed to write during the first 15 minutes. This time is to be spent in reading
More informationINTERNATIONAL INDIAN SCHOOL, RIYADH STD: X SUBJECT- CHEMISTRY CHAPTER 1: CHEMICAL REACTIONS WORKSHEET #1
INTERNATIONAL INDIAN SCHOOL, RIYADH STD: X SUBJECT- CHEMISTRY CHAPTER 1: CHEMICAL REACTIONS WORKSHEET #1 I) Very Short Type Questions (1 mark) 1. What is the relationship between decomposition and combustion
More informationCompiled by Rahul Arora What do you mean by corrosion? How can you prevent it?
Rahul Arora 12. What do you mean by corrosion? How can you prevent it? 13. MnO2 + 4HCl MnCl2 + 2H2O + Cl2 In the above equation, name the compound which is oxidized and which is reduced? 14. Match the
More informationThe ion with Vanadium in its oxidation state of 5 exists as a solid compound in the form of a VO 3
Chemistry of some Transition elements: V, Mn, Co, Cu, Cr and Ag Vanadium Vanadium has four main oxidation states. Each one has a different colour. VO 2 VO 2 V 3 V 2 O.N. 5 yellow O.N. 4 blue O.N. 3 green
More informationAnalysis of group III
1 Analysis of group III Radicals Fe 3+, Al 3+ and Cr 3+ Group Reagent NH4OH in presence of NH4Cl Principle: Hydroxides of Fe 3+, Al 3+ and Cr 3+ are insoluble in water. In presence of NH4Cl, NH4OH is feebly
More informationChapter: The d and f Block Elements
Chapter: The d and f Block Elements Introduction to d block elements Question 1 In Tc ( Z = 43) and Tb( Z = 65) which one is inner transition metal and which one is transition metal and why? The outer
More informationSn 2+ (aq) + 2 Ag + (aq) Sn 4+ (aq) + 2 Ag(s),
1. Which change in oxidation number represents oxidation? A) Sn 2+ (aq) Sn 4+ (aq) B) Sn 2+ (aq) Sn(s) C) Sn 4+ (aq) Sn 2+ (aq) D) Sn 4+ (aq) Sn(s) E) Sn(s) Sn 2 (aq) 2. In the reaction Sn 2+ (aq) + 2
More informationJSUNIL TUTORIAL, SAMASTIPUR
Chapter 1 Chemical Reactions and Equations Q 1. Why should a magnesium ribbon be cleaned before burning in air? Ans. Before burning in air, the magnesium ribbon is cleaned by rubbing with a sandpaper.
More informationMR. D HR UV AS HE R I.C.S.E. BOA RD PAP ER ICSE
MR D HR UV AS HE R ICSE BOA RD PAP ER 200 4 1 ICSE-2004 Section A (40 Marks) (Attempt all questions from this section) Question 1 (a) Choose the letters A,B,C or D to match the descriptions (i) to (iv)
More informationEquilibria of Slightly Soluble Ionic Compounds: We lied to you in chem 115
Precipitation Reactions Predicting Whether a Precipitate Will Form Note the ions present in the reactants Consider all possible cation-anion combinations Use the solubility rules to decide whether any
More informationOxidation and Reduction
Oxidation and Reduction An oxidation reaction is one in which oxygen is added to a substance. Example: Methane is oxidised when it burns in air. Oxygen is added to the carbon in methane, forming carbon
More informationNew Requirements and Methods for Chromium Sampling and Analysis
Chubb Global Risk AdvisorsSM Advisory Series New Requirements and Methods for Chromium Sampling and Analysis 1 Due to recent significant reductions in the Threshold Limit Values (TLV) for hexavalent chromium,
More informationChemical reactions and electrolysis
Chemical reactions and electrolysis Higher Revision Questions Name: Class: Date: Time: 95 minutes Marks: 95 marks Comments: Page of 29 (a) Magnesium metal is shaped to make magnesium ribbon. Explain why
More informationThe oxides of nitrogen and the details of the oxygen states of nitrogen and the N:O ratio can be presented in a tabular form as:
Oxides of Nitrogen Introduction to oxides of nitrogen Nirogen has a position in second period of group V in the modern periodic table. It has molecular formula N2. It has atomic number 7 and atomic weight
More informationSolubility Equilibrium
Solubility Equilibrium This is an X-ray of the large intestine. The patient was given a drink of barium sulfate to drink which is insoluble (does NOT dissolve) and gives the doctor a better image. Barium
More informationLearn Chemistry. Starter for Ten 9. Redox. Registered Charity Number
Learn Chemistry Starter for Ten 9. Redox Developed by Dr Kristy Turner, RSC School Teacher Fellow 2011-2012 at the University of Manchester, and Dr Catherine Smith, RSC School Teacher Fellow 2011-2012
More informationSodium Peroxides (Na 2 O 2 ): Preparation: It is formed by heating the metal in excess of air or oxygen at 300, which is free from
S-Block Elements Generally one question was asked every year from this topic. This is completely theoretical and little memory based. Last minute revision generally helps. The general trends in the properties
More informationThis is used to detect nitrogen, halogen and sulphur present in organic compound.
Qualitative Analysis of Organic Compounds: This is used to detect nitrogen, halogen and sulphur present in organic compound. a) Sodium Extract: Aqueous solution containing soluble sodium salt of the elements
More informationMARK SCHEME for the May/June 2007 question paper 0620 CHEMISTRY
UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS International General Certificate of Secondary Education MARK SCHEME for the May/June 2007 question paper 0620 CHEMISTRY 0620/03 Paper 3 (Extended Theory),
More informationIntroduction to Metallurgy
Metallurgy Introduction to Metallurgy Metallurgy deals with extraction and purification of metals from their sources. Very few metals like gold, silver etc. occur in native state, while most other metals
More informationCHEMISTRY PAPER 1998
CHEMISTRY PAPER 1998 (One Hour and a Half) Answer to this paper must be written on the paper provided separately. You will NOT be allowed to write during the first 15 minutes. This time is to be spent
More information1. The equation that represents the equilibrium in a saturated solution of Fe 2 (SO 4 ) 3 is.. The precipitate which forms first is
CHEMISTRY 12 UNIT 3 - REVIEW Ksp Part A - Multiple Choice 1. The equation that represents the equilibrium in a saturated solution of Fe 2 (SO 4 ) 3 is A. Fe 2 (SO 4 ) 3 (s) 3 Fe 2+ (aq) + 2 SO 4 3 (aq)
More informationI. PHYSICAL PROPERTIES. PROPERTY METALS NON-METALS 1.Lustre Metals have shining surface. They do not have shining surface.
Elements can be classified as metals and non-metals on the basis of their properties. Example of some metals are : Iron (Fe), Aluminium (Al), Silver (Ag), Copper (Cu) Examples of some non-metals are :
More informationWhich of these is the formula for disulfur heptoxide? A. S 2 O 7 B. S 7 O 2 C. SO 2 D. N 2 O
Which of these is the formula for disulfur heptoxide? A. S 2 O 7 B. S 7 O 2 C. SO 2 D. N 2 O Which of these is the correct chemical formula for a molecule of oxygen? A. O B. O -2 C. O +2 D. O 2 Which of
More information1. Which of the given statements about the reaction below are incorrect?
1. Which of the given statements about the reaction below are incorrect? 2PbO(s) + C(s) 2Pb(s) + CO 2 (g) a. Lead is getting reduced b. Carbon dioxide is getting oxidised c. Carbon is getting oxidised
More informationThermal decomposition. Metal carbonates
Decomposition reactions Copy correctly Up to 3% of a workbook Copying or scanning from ESA workbooks is subject to the New Zealand Copyright Act which limits copying to 3% of this workbook. Many compounds
More informationMETALS AND THEIR COMPOUNDS
METALS AND THEIR COMPOUNDS Metals are elements whose atoms ionize by electron loss, while non-metals are elements whose atoms ionize by electron gain. Metals are in groups 1, 2 and 3 of the periodic table.
More informationBoiling point in C. Colour in aqueous solution. Fluorine 188 colourless. Chlorine 35 pale green. Bromine X orange.
Q1.This question is about halogens and their compounds. The table below shows the boiling points and properties of some of the elements in Group 7 of the periodic table. Element Boiling point in C Colour
More informationName: Date: Period: Page: Predicting Products. Predict the products, and balance each reaction. Use the reaction type as a hint.
Name: Date: Period: Page: Predicting Products Predict the products, and balance each reaction. Use the reaction type as a hint. For reactions with a transition metal, the most likely charge on the metal
More informationReactivity Series. Question Paper. Cambridge International Examinations. Score: /39. Percentage: /100
Reactivity Series Question Paper Level Subject Exam oard Topic Sub-Topic ooklet O Level hemistry ambridge International Examinations Metals Reactivity Series Question Paper Time llowed: 47 minutes Score:
More information6 METALS & NON METALS
Grade-8 Chemistry Chapter- 6 METALS & NON METALS 1. What happens in each of the following cases? a) Magnesium is burnt in oxygen. Ans: When magnesium burns in oxygen it produces magnesium oxide with dazzling
More information2.4 Period 3. Na Mg Al Si P S Cl Ar
2.4 Period 3 Period 3 Na Mg Al Si P S Cl Ar Periodicity: Periodicity: The repeating trends in physical and chemical properties of elements as you go across the Periodic Table Periods often show gradual
More informationAnalysis of group IV Radicals
1 Analys of group IV Radicals Radicals : Zn 2+, Ni 2+, Co 2+ and Mn 2+ Group reagent : H2S in presence of NH4OH. Precipitate : Sulphides of Zn 2+, Ni 2+, Co 2+ or Mn 2+ Principle: In alkaline medium, H2S
More informationICSE-Science 2 (Chemistry) 2000
ICSE-Science 2 (Chemistry) 2000 Answers to this Paper must be written on the paper provided separately. You will not be allowed to write during the first 15 minutes. This time is to be spent in reading
More informationSolutions Unit Exam Name Date Period
Name Date Period Ms. Roman Page 1 Regents Chemistry 1. Which mixture can be separated by using the equipment shown below? 6. Which ion, when combined with chloride ions, Cl, forms an insoluble substance
More informationClass: Target IIT-JEE 2017
ass: 10 + 2 Target IIT-JEE 2017 PPER 1 (8.1.2016) Section (Single Correct) egative Marking [-1] This Section contains 5 multiple choice questions. Each question has four choices ), ), C) and D) out of
More informationExercise 6a. Balancing equations
Exercise 6a Balancing equations Balance the following equations. To get you started _ indicates the first six questions where numbers need to be inserted to achieve the balance. In one or two difficult
More informationGraspIT AQA GCSE Chemical changes
A. Reactivity of metals The reactivity series, metal oxides and extractions 1. Three metals, X, Y and Z were put into water. The reactions are shown below: a) Use the diagrams to put metals X, Y and Z
More informationChapter 17 Solubility and Complex Ion Equilibria
Chem 1046 General Chemistry by Ebbing and Gammon, 8th Edition Prof George W.J. Kenney, Jr Last Update: 27Nov2008 Chapter 17 Solubility and Complex Ion Equilibria These Notes are to SUPPLIMENT the Text,
More informationDouble Award Science: Chemistry
New Specification Centre Number Candidate Number General Certificate of Secondary Education 2014 2015 Double Award Science: Chemistry Unit C1 Higher Tier ML [GSD22] WEDNESDAY 25 FEBRUARY 2015, MORNING
More informationQ1. From the following list of substances, choose the substances which meet the description given in parts (i) to (v) below :
Questions:- Q1. From the following list of substances, choose the substances which meet the description given in parts (i) to (v) below : Ammonium chloride, ammonium nitrate, chlorine, dilute hydrochloric
More informationClass XII Chemistry Chapter 8. The d and f-block Elements. Top Concepts
1 Class XII Chemistry Chapter 8 The d and f-block Elements Top Concepts 1. d -Block elements: The elements lying in the middle of periodic table belonging to groups 3 to 12 are known as d block elements.
More informationEXERCISE. Question 8.1: Write down the electronic configuration of: Cr 3+ + (iii) Cu + (v) Co 2 + (vii) Mn 2+ Pm 3+ (iv) Ce 4+ (vi) Lu 2+ (viii) Th 4+
EXERCISE Question 8.1: Write down the electronic configuration of: Cr 3+ + (iii) Cu + (v) Co 2 + (vii) Mn 2+ Pm 3+ (iv) Ce 4+ (vi) Lu 2+ (viii) Th 4+ Cr 3+ : 1s 2 2s 2 2p 6 3s 2 3p 6 3d 3 Or, [Ar] 18 3d
More informationcarbon anode/+ (1) electrolyte Al 2 O 3 with or dissolved in or solution in cathode/ (1) (steel outer)
1. Aluminium occurs as bauxite, which contains aluminium oxide with impurities mainly of iron (III) oxide and silica. (a) (b) (c) Outline how bauxite is processed to give pure aluminium oxide, showing
More informationGENERAL PRINCIPLES AND PROCESSES OF ISOLATION OF ELEMENTS
INTEXT QUESTIONS GENERAL PRINCIPLES AND PROCESSES OF ISOLATION OF ELEMENTS Question 6.1: Which of the ores mentioned in Table 6.1 can be concentrated by magnetic separation method? If the ore or the gangue
More information1 Class XII Chemistry Chapter 8 The d and f-block Elements Top Concepts 1. d -Block elements: The elements lying in the middle of periodic table belonging to groups 3 to 12 are known as d block elements.
More informationTopic Reacting masses Level GCSE Outcomes 1. To calculate reacting masses 2. To set out mole calculations in a grid format
Topic Reacting masses Level GCSE Outcomes 1. To calculate reacting masses 2. To set out mole calculations in a grid format Problems on Reacting Masses of Solids Section 1 1. What is the mass of magnesium
More information6. HYDROGEN AND IT S COMPOUNDS
. YDROGEN AND IT S COMPOUNDS PREVIOUS EAMCET BITS Which of the following reactions represents the oxidizing property of O ( 008) 1) KMnO + + 5 KSO + MnSO + 8 + 5O K ) Fe CN + KO + O K Fe CN + O + O ) PbO
More information(a) To find out which is the more reactive metal, zinc or tin, the following experiment could be carried out. piece of zinc shiny surface
1 The reactivity series lists metals in order of reactivity. (a) To find out which is the more reactive metal, zinc or tin, the following experiment could be carried out. piece of zinc shiny surface tin(ii)
More informationElectrochemistry Written Response
Electrochemistry Written Response January 1999 7. Balance the following redox reaction in acidic solution: RuO 4 + P Ru(OH) 2 2+ + H 3 PO 3 (acid) (3 marks) 8. A technician tests the concentration of methanol,
More information85 Q.14 In which of the following substances does nitrogen have the lowest oxidation number?
Redox and electrolysis / Section 3 / Sect3pp.doc / S. W. Tse / P.1 85 Q.5 The element with an atomic number of 19 is likely to be A. an oxidizing agent. B. a reducing agent. C. a non-metal. D. chemically
More informationElectricity and Chemistry
Electricity and Chemistry Electrochemistry: It is a branch of chemistry that deals with the reactions involving the conversion of chemical energy into electrical energy and vice-versa. Electrochemical
More informationOur country, our future S2 CHEMISTRY DURATION: 2 HOUR
Our country, our future S2 CHEMISTRY Exam 1 DURATION: 2 HOUR INSTRUCTIONS: This paper consists of two sections A and B, Attempt all questions in section A and B For section A, circle the most correct alternative
More informationSample Answers/Solutions - Study of Compounds
Sample Answers/Solutions - Study of Compounds Hydrogen Chloride 1. It is a gas at room temperature. 2. Refer to pg.128 right side section 2. 3. If the reaction is carried out above 200 o C, then the by-product
More informationd-block ELEMENTS 1. INTRODUCTION
d-block ELEMENTS 1. INTRODUCTION The element lying between s- and p-block element of the periodic table are collectively known as transition or transitional elements. (T.E'.S.) Their properties are transitional
More informationChemistry Test Paper
Chemistry Test Paper [Time:1 1 hrs] [M. Marks : 80] 2 Answers to this paper must be written on the paper provided separately. You will not be allowed to write during the first 15 minutes. This time is
More informationTest sticks and test papers for semi-quantitative determinations
QUANTOFIX test sticks for semi-quantitative determinations QUANTOFIX test sticks meet the most important requirements for a modern quick-test: rapid dip and read convenient the analysis can be carried
More informationHYDROGEN AND ITS COMPOUNDS
HYDROGEN AND ITS COMPOUNDS Short Answer Questions: 1. Write any two methods for the preparation of H 2 O 2? Ans. I) Electrolytic Method: Hydrogen peroxide is manufactured on a large scale by the electrolysis
More informationQuestion 6.1: Copper can be extracted by hydrometallurgy but not zinc. Explain. The reduction potentials of zinc and iron are lower than that of copper. In hydrometallurgy, zinc and iron can be used to
More informationModule: 4 Lecture: 17
Module: 4 Lecture: 17 SULFURIC ACID INTRODUCTION Sulfuric acid (H2SO4) is a highly corrosive strong mineral acid. It is a colorless to slightly yellow viscous liquid which is soluble in water at all concentrations.
More informationDURATION: 1 hour 30 minutes
Our country, our future 545/1 S4 CHEMISTRY Exam 16 PAPER 1 DURATION: 1 hour 30 minutes Instructions This paper consists of fifty (50) objective questions. All questions are compulsory Answer the questions
More informationGeneral Principle of Isolation of Elements (NCERT)
Question 6.1: Copper can be extracted by hydrometallurgy but not zinc. Explain. The reduction potentials of zinc and iron are lower than that of copper. In hydrometallurgy, zinc and iron can be used to
More informationKenya Certificate of Secondary Education (K.C.S.E.)
Name: Index No. School:. Candidate s Sign.... Date:... 233/2 CHEMISTRY PAPER 2 JULY/AUGUST 2011 TIME: 2 HOURS Kenya Certificate of Secondary Education (K.C.S.E.) Chemistry Paper 2 INSTRUCTIONS TO CANDIDATES:
More informationName: Mods: Date Agenda Homework
Name: Mods: UNIT 6 FORMULA WRITING, FORMULA WEIGHTS, and PERCENT COMPOSITION Date Agenda Homework Wed Dec 3 Thurs Dec 4 Fri Dec 5 Mon Dec 8 Tues Dec 9 Wed Dec 10 (1/2 Day) Thurs Dec 11 Fri Dec 12 Mon Dec
More informationOur country, our future 545/1 S4 CHEMISTRY PAPER 1 DURATION: 2 HOUR
Our country, our future 545/1 S4 CHEMISTRY Exam 1 PAPER 1 DURATION: 2 HOUR Instructions: Attempt all questions Circle the most connective alternative with either a blue or black ink-but not a pencil. 1.
More informationVery high purity silicon required for making semiconductors is obtained by reduction of highly purified SiCl 4
1 Silicon and its compounds Silicon, being a second member of group 14, has a much larger size and lower electronegativity than hat of carbon As a result silicon does not form double bond with itself or
More informationJSTSE : PREVIOUS YEARS
JSTSE : PREVIOUS YEARS CHEMISTRY (2014) 91. In paints dispersed phase and dispersion medium are (1) solid and liquid (2) liquid and solid (3) liquid and liquid (4) gas and liquid 92. Which statement is
More informationApplications of Oxidation/Reduction Titrations. Lecture 6
Applications of Oxidation/Reduction Titrations Lecture 6 Pretreatmentauxiliary oxidizing/reducing reagent Ex: when a sample containing iron is dissolved, the resulting solution usually contains a mixture
More informationCHEMISTRY. SECTION I (40 Marks) Attempt all questions from this Section
CEMISTRY SCIENCE Paper 2 (One hour and a half) Answers to this Paper must be written on the paper provided separately. You will not be allowed to write during the first 15 minutes. This time is to be spent
More informationI. PHYSICAL PROPERTIES PROPERTY METALS NON-METALS
Elements can be classified as metals and non-metals on the basis of their properties. Example of some metals are : Iron (Fe), Aluminium (Al), Silver (Ag), Copper (Cu) Examples of some non-metals are :
More informationPRECAUTIONS WHILE PERFORMING CHEMISTRY ACTIVITIES. Do not touch anything without the permission of the teacherin the lab.
PRECAUTIONS WHILE PERFORMING CHEMISTRY ACTIVITIES Do not touch anything without the permission of the teacherin the lab. 1. Do not use conc. Acids as they are harmful. 2. Handle glass material with care.
More informationCHEMGGURU.ORG YOUTUBE: CHEMGGURU
Q 8.1: Write the electronic configuration of: (i) Th 4+ (ii) Lu 2+ (iii) Ce 4+ (iv) Pm 3+ (v) Mn 2+ (vi) Co 2 + (vii) Cu + (viii) Cr 3+ + (i) Th 4+ : 1s 2 2s 2 2p 6 3s 2 3p 6 3d 10 4s 2 4p 6 4d 10 4f 14
More informationDuncan. UNIT 8 - Chemical Equations BALANCING EQUATIONS PRACTICE WORKSHEET 14.) C2H6 + O2 CO2 + H2O. 2.) Na + I2 NaI 3.) N2 + O2 N2O 4.
BALANCING EQUATIONS PRACTICE WORKSHEET 1.) CH4 + O2 CO2 + H2O 2.) Na + I2 NaI 3.) N2 + O2 N2O 4.) N2 + H2 NH3 5.) KI + Cl2 KCl + I2 6.) HCl + Ca(OH)2 CaCl2 + H2O 7.) KClO3 KCl + O2 8.) K3PO4 + HCl KCl
More informationClass 10 Science NCERT Exemplar Solutions Chemical Reactions And Equations
Class 10 Science NCERT Exemplar Solutions Chemical Reactions And Equations Short Answer Type Questions 1. Write the balanced chemical equations for the following reactions and identify the type of reaction
More informationBalance the following equations: 1. Al + N 2 AlN. 2. Fe + O 2 Fe 3 O CaCO 3 CaO + CO 2 4. NH 4 NO 3 N 2 O + H 2 O. 5. KI + Cl 2 KCl + I 2
Balance the following equations: 1. Al + N 2 AlN 2. Fe + O 2 Fe 3 O 4 3. CaCO 3 CaO + CO 2 4. NH 4 NO 3 N 2 O + H 2 O 5. KI + Cl 2 KCl + I 2 6. Pb(NO 3 ) 2 + HCl PbCl 2 + HNO 3 7. BaO 2 BaO + O 2 8. Al
More information9.2.1 Similarities and trends in the properties of the Group II metals magnesium to barium and their compounds
9.2 Group II Content 9.2.1 Similarities and trends in the properties of the Group II metals magnesium to barium and their compounds Learning Outcomes Candidates should be able to: (a) (b) (c) (d) describe
More informationNCERT solutions for Metals and Non Metals
NCERT solutions for Metals and Non Metals 1 Question 1 Give an example of a metal which (i) is a liquid at room temperature. (ii) can be easily cut with a knife. (iii) is the best conductor of heat. (iv)
More informationProperties A Metal B Non- metal Electronic configuration?? Nature of oxides?? Oxidizing or reducing action?? Conduction of heat and electricity??
CLASS: X NCERT (CBSE) SCIENCE: Chemistry Page: 1 Question 1: Compare the properties of a typical metal and a non-metal on the basis of the following. Fill in Column A, B. Properties A Metal B Non- metal
More informationd-block AND f-block ELEMENTS
d-block and f-block Elements MODULE - 6 21 d-block AND f-block ELEMENTS You have already learnt in lesson 3 on periodic classification, that each period (except the first period) of the periodic table
More informationGRADE: 10 CHEMISTRY MCQ (TERM-1)
GRADE: 10 CHEMISTRY MCQ (TERM-1) 1 When ferrous sulphate crystals are heated, the colour of the residue formed is : (a) red (b) brown (c) orange (d) green. 2 A small amount of quick lime is taken in a
More informationSOLUBILITY STUDY GUIDE- Multiple Choice Section
SOLUBILITY STUDY GUIDE- Multiple Choice Section Multiple Choice Section: This study guide is a compilation of questions from provincial exams since 2000. I urge you to become intimately familiar with question
More informationThe s-block elements: Alkali and alkaline earth metals
The s-block elements: Alkali and alkaline earth metals Alkali metals The s-block elements:alkali and alkaline earth metals othe alkali family is found in the first column of the periodic table include;
More informationINDIAN SCHOOL MUSCAT SENIOR SECTION DEPARTMENT OF CHEMISTRY CLASS X- PRACTICAL WORKSHEET
INDIAN SCHOOL MUSCAT SENIOR SECTION DEPARTMENT OF CHEMISTRY CLASS X- PRACTICAL WORKSHEET Different types of chemical reactions Experiment No: 1(a) Combination reaction Objectives: To study the Combination
More informationPrecipitation Reactions and Gravimetric Analysis
Precipitation Reactions and Gravimetric Analysis Titrations where the titrant forms a precipitate with the analyte. Not always so straightforward a number of requirements need to be met. Precipitation
More informationCompounds & Reactions Week 1. Writing Formulas & Balancing Equations. Write the chemical formula for each molecular (covalent) compound.
Compounds & Reactions Week 1 Name Writing Formulas & Balancing Equations Write the chemical formula for each ionic compound. 1. Lithium fluoride 2. Copper (II) chloride 3. Manganese (II) oxide 4. Potassium
More informationANALYTICAL LABORATORY MANUAL I QUALITATIVE ANALYSIS OF ANIONS CATIONS
ANALYTICAL LABORATORY MANUAL I QUALITATIVE ANALYSIS OF ANIONS CATIONS ANKARA UNIVERSITY, FACULTY OF PHARMACY DEPARTMENT OF ANALYTICAL CHEMISTRY TABLE OF CONTENTS 1) QUALITATIVE ANALYSIS OF ANIONS... 2
More informationINTERPRETING CHEMICAL FORMULAS AND SYMBOLS
INTERPRETING CHEMICAL FORMULAS AND SYMBOLS THE FORMULA OR SYMBOL REPRESENTS: CHEMICAL FORMULA OR SYMBOL NUMBER OF ATOMS TOTAL CHARGE NUMBER OF PROTONS NUMBER OF ELECTRONS Atom Molecule Monatomic Cation
More informationFormula & Equation Writing
Formula & Equation Writing Book column Be Na Mg column Ca lithium Ionic Equations Ionic Formulae Balanced Equations Formula Equations Word Equations carbonate Transition Metals C 3 valency valency Using
More informationMAIN GROUPS CHEMISTRY. Alkaline Earth Metals ( Group IIA)
MAIN GROUPS CHEMISTRY Alkaline Earth Metals ( Group IIA) INTRODUCTION The group 2 elements comprise beryllium, magnesium, calcium, strontium, barium and radium. They follow alkali metals in the periodic
More informationToday! Demonstrations of Redox Chemistry! Electrochemistry! electrons moving about! equilibrium with a control knob! The disappearing Aluminum Rod!
Today! Electrochemistry! electrons moving about! equilibrium with a control knob! Redox chemistry! oxidation and reduction! Demonstrations of Redox Chemistry! The disappearing Aluminum Rod! Alkali Metals
More information