Acids, Bases and Salts:Solved Exercise and Think-Tank

Question 2: Give short answers.

I. Write the equation for the self ionization of water.

Answer.

H2O + H2O -----------> H3O+ + OH

ii. Define and give examples of arrhenius acids.

Answer.

A substance that ionizes in water to produce H+ is called Arhenius acid. For example,

HCl -----------H2O--------> H+ + Cl-

Acid

H2SO4 ----------H2O--------> 2H+ + SO42-

Acid

iii. Why H+ act as Lewis acis?

Answer. According to Lewis concept, a Lewis acid is a substance that can accept electron pair. H+ acts as a Lewis acid because it has no electron in it valence shell. When it reacts with a a specie with a lone pair of electrons, it accepts that lone pair of electrons. So H+ is a Lewis acid.

For example,

H+ + NH3 ---------> NH4+

Lewis acid

iv. Why NH3 acts as a bronsted lorry base?

v. Why BF3 x as Lewis acid?

Question 3: ammonium Hydroxide and nitric acid react and produce Ammonium Nitrate and water write balanced chemical equation for this neutralization reaction.

Question 4: write balanced chemical equation for the following neutralization reactions.

I. Sulphuric acid + magnesium hydroxide ------> Magnesium sulphate + water

ii. Sulphuric acid + sodium hydroxide ---------> sodium sulphate + water

iii. Hydrochloric acid + calcium hydroxide -------> calcium chloride + water

Question 5: identify bronsted lorry assets are bases in the following reactions.

ii.

Question 6 Identify Lewis acid and Lewis base in the following reactions

Question 7: classify the following solution as a basic or neutral.

I. A slution that has hydrogen ion concentration 1. 0 × 10-3 M

iii. A slution that has hydrogen ion concentration 1. 0 × 10-10 M

iii. A slution that has hydroxyl ion concentration 1. 0 × 10-3 M

iv. A slution that has hydroxyl ion concentration 1. 0 × 10-10 M

Question 8: Classify following substances as Lewis acid and bases.

NH3, F- , H2O, BF3

Question 9: Give the Bronsted-Lowery definition of an acid.

Write an equation that illustrate the definition.

Question 10: identify bronsted assets and bronsted bases in the following reactions

I CH3COOH + H2O --------> CH3COO- + H3O+

ii. HCO3- + H2O ----------> CO32- + H3O+

iii. NH3 + H2O --------------> NH4+ + OH-

iv. HCl + HCO3- ----------> H2CO3 + Cl-

v. Hs- + H2O -----------> S-2 + H3O

Question 11 identify the Lewis acid and Lewis basis in the following reactions.

I. H+ + CN- ----------> HCN

ii. B(OH)3 + OH- -----------> B(OH)4-

iii. Cu+2 + 4NH3 ----------> [ Cu(NH3)4]+2

iv. OH- + Al(OH)3 ----------> Al(OH)4-

Question 12:

Identify Lewis acids and Lewis basis for from the following

AlCl3, Ag+ , CH3-OH, CH3-NH2, FeCl3

Question 13: classify water as Proton donor or Proton acceptor.

Question 14: write equations showing the ionization of the following as a genius acids.

a. HI b. HNO2

Question 15: write equations showing the ionization of the following as bronstellary acids.

a. HNO2 b. HCN

Think Tank

Question 16: compare the relative concentration of hydrogen ion and hydroxyl ion in the each case of solution.

a. Acidic b. Basic c. Neutral

Question 17. Codeine C18H21NO3 is a commonly prescribed painkiller a dissolve inverter by the following reaction

C18H21NO3 + H2O ---------> [C18H21HNO3]+ + OH-

Differentiate codeine and water as Bronsted acid or base.

Question 18 examine some ways in which you might determine whether a particular water solution contains and acid are base

Question 19. The tables below shows the colours of the two indicators in acid and alkaline solution.

Indicator colour in acidic solution colour in basic solution

A Red Blue

B. Colourless Red

a. Predict the colour of the indicator A?

i in a solution of pH 3

ii. in a solution of pH 10

iii. Predict the colour of indicator B in a solution of PH 5.

iv. When a few drops of indicator B are placed in a solution X it turns red image evaluate the properties of solution X.

Question 20: bacteria in our mouth feed on small particles of food stuck to our teeth and change it into acid at toothpaste of PS 10 can help to prevent the Acer from damaging our teeth Defend the statement.

Question 21: can a substance be elevated without being bronsted lorry yesterday

Comments

Class 9 Chemistry Notes for Federal Board

Class 9 Chemistry Notes for Federal Board Introduction Class 9 Chemistry notes for the Federal Board have been written according to the National Curriculum 2006. It develops various skills such as questioning, observations, predicting, measuring, classifying, designing experiments, analyzing and interpreting the data. among students. We have made these notes very simple. After reading these notes, students can easily understand all topics. Students can answer all types of questions including essay type, short and multiple choice, self assessments and think tank. We have also solved exercises according to the Federal board examination pattern. Students, after going through 9th class chemistry notes can get maximum marks in their exams. They can lay down a strong foundation of scientific knowledge among students. In future, notes for class 9 will be available in pdf format. Students will be able to note pdf free download very soon. Students will ha...

Class 10 Chemistry Notes for Federal Board

Class 10 Chemistry Notes for Federal Board Introduction Class 10 Chemistry Notes for Federal Board have been written according to the National Curriculum 2006. These notes will make students able to learn topics by their own. 10th class notes for all chapters are very and easy to understand. After studying these notes, students will become confident to answer all type of questions. Chemistry notes for class 10 provide solution to all kinds of questions including essay type, short and multiple choice, self assessments and think tank. These notes also contain all past papers of reduced syllabus as well as complete syllabus. Soon, students will have access to 10th class chemistry notes in Urdu pdf download form. We are also working hard to provide all chemistry notes in pdf format and student will be able to download these notes. We also trying to upload video lectures about class 10 chemistry. Don't forget, you can test your chemistry by using online test. Fu...

Theories of Covalent Bonding and Shapes of Molecules: MCQs

chemicalAlgebra 1. The bond energies of F 2 , Cl 2 , Br 2 and I 2 are 37, 58, 46 and 36 Kcal, respectively. The strongest bond is formed in A) F 2 B) Cl 2 C) Br 2 D) I 2 ... Answer is B) Description: The bond energy is proportional to bond length. So, the bond strength of Cl 2 is higher. show Answer 2. The percentage of ionic character of bond between two atoms is calculated from the difference between their A) Ionic B) Electronegativities C) Electron affinities D) Ionization energies ... Answer is B) Description: The percentage of ionic character depends upon the difference of E.N. difference between the bonded atom. Greater the E. N. difference, greater the ionic character and hence greater the bond energy show Answer 3. The geometry of PF 5 molecule is A) Planer B) Square planer C) Trigonal pyramidal D) Tetrahedral ... Answer is C) Description: ...

Chemistry

T he Federal Board of Intermediate & Secondary Education (FBISE) is an autonomous body that conducts the examinations in the institutions affiliated with it in Pakistan as well as abroad. Punjab government has ten boards of Intermediate & Secondary Education including Bahawalpur Board, D.G. Khan Board, Faisalabad Board, Gujranwala Board, Lahore Board, Multan Board, Rawalpindi Board and Sargodha Board and each board conducts exams independently. Federal Board generally follows the international norms and standards. Federal Board paper pattern is quite tricky and similar to O-Level and A Level formats. These questions need conceptual approach to be solved. Punjab board’s Paper pattern is comparatively easy up to some extent. We are currently focusing on the subject of Chemistry for all classes affiliated with Federal Board ( IX , X , XI , XII ) and Punjab Board ( XI XII ). We intend to extend it to all subjects i...

Basic Definitions| Matter, Substance, Element, Compound. Mixture, Homogeneous mixture and Heterogeneous mixture Examples (for Grade - 9 students)

Basic Definitions| Matter, Substance, Element, Compound. Mixture, Homogeneous mixture and Heterogeneous mixture Examples (for Grade - 9 students) Question: Define following terms: Matter Substance Element Compound Mixture Homogeneous mixture Heterogeneous mixture Answer Matter: Matter can be anything that occupies space (volume) and has mass. Example, book, table, walls, chairs, plants, animal, etc. Substance: Substance is a matter that has a particular set of characteristics that differ from the characteristics of another kind of matter. For example, oxygen, water, carbon monoxide, carbon dioxide, urea, glucose, common salt etc are different substances. Element: A substance that cannot be converted to other simpler substances is known as an element. or A substance which has all atoms of same atomic number is called element. For example substances like oxygen, hydrogen, iron, copper, aluminum etc. are elements. Compound: ...

Experimental Techniques in Chemistry

Analytical Chemistry: The branch of chemistry that deals with the quantitative and qualitative analysis of substances is called Analytical Chemistry. Question 2.1: What is difference between quantitative and quantitative analysis? What are various steps involved in quantitative analysis? Answer: Qualitative analysis: The analysis in which elements are identified is called qualitative analysis. Quantitative analysis: The analysis in the form of which relative amounts of elements are determined is called quantitative analysis. There are four main steps involved in quantitative analysis. 1. Obtaining a sample for analysis 2. Separation of desired constituent 3. Measurement and calculations of results 4. Drawing conclusions from analysis Question 2.2: Define filtration. How do we select the filter media? Answer: The process of separating solids or suspended particles from liquids by using a filter medium is called filtration. Question...

Alkyl halides

The compounds in which one hydrogen atom of alkane is replaced by a halogen atom is called alkyl halide. Alternatively, The halogen derivatives of alkanes with general formula R-X are Halide called alkyl halide. For example CH4 ( Alkane ) CH3-X ( Alkyl halide ) X = F, Cl, Br and I Table Of Contents Types Mono, di, tri or poly haloalkane depending upon the number of halogen atom. For example C lassification of Alkyl Halides Alkyl halides can be classified as primary, secondary and Tertiary alkyl halides. 1. Primary Alkyl Halides The alkyl halides in which a halogen atom is bonded with primary carbon is called primary alkyl halide. Primary carbon is the carbon that is attached one or no carbon atom. The Secondary Alkyl Halides The alkyl halides in which a halogen atom is bonded with secondary carbon ...

CHAPTER # 15 ORGANIC COMPOUNDS

ORGANIC COMPOUNDS Modern definition. C ompounds of carbon, hydrogen and their derivatives, are called organic compounds. For example, CH 4 , CH 3 Cl etc. Contents Sources of organic Compounds: Following are the main sources of organic compounds: i. Fossil fuels or Fossil remains. ii. Plants and Natural product iii. Partial &Total Synthesis iv. Fermentation and Biotechnology Fossil fuels or Fossil remains: The main sources of fossil fuels or fossil remains are: a. coal b. petroleum c. gas a. Coal: Coal is one of the organic compounds. Coal major source of into coke, and coal law" on pyrolysis Com can be converted destructive distillation. More than 200 organic compounds" have been directly isolated from coal tar, which are used. in ...drug. dyes, other. preparation of perfumes.. photographic developers and. b. Petroleum: Petroleum Sticky Liquid ground in that is block Thick seeps out of the s...

Shielding Effect (Grade 9 Students) and its trend in Periodic Table.

Question: What is shielding effect? Give its trends in the periodic table. Answer . Shielding Effect The decrease in force of attraction between nucleus and valence electrons due to presence of inner shell electrons is called shielding effect. It is also known as screening effect. It increases with increase in inner shell electrons. For example, Mg has greater shielding effect than Be. This is because Mg has eight more inner-shell electrons than Be. Trend in Periodic Table In period As we move from left to right in a period, shielding effect remains constant. Reason is that the number of inner shell electrons remains constant along the period. In group As we move from top to bottom in a group, shielding effect increases. This is due to fact that the number of inner shell increases and hence, inner shell electrons also increase. For example, Na has greater shielding effect than Li because of eight more inner shell electrons than Li...

Class 9 Electrochemistry MCQs and Answers with explanation

1. In which of the following changes, the nitrogen atom is reduced? a) N 2 to NO b) N 2 to NO 2 c) N 2 to NH 3 d) N 2 to HNO 3 ... Answer is b) Explanation: Oxidation number of an elemnet in free state is zero. So Oxidation No. of N 2 = 0 Calculate oxidation No. of nitrogen in each compound. Option a) Let, oxidation No. of N in NO is X. Sum of oxidation numbers of all atoms present in a neutral compound is zero. Oxidation No. of N + (Oxidation No. of O ) = 0 X-2 = 0 X = +2 X = +2 Oxidation No. of N in NO 2 is +2 Option b) Let, oxidation state of N in NO 2 is X. Sum of oxidation numbers of all atoms present in a neutral compound is zero. Oxidation No. of N + 2(Oxidation No. of O ) = 0 X + 2(-2) = 0 X -4 = 0 X = +4 Oxidation No. of N in NO 2 is +4 Option c) Let, oxidation state of N in NH 3 is X. Sum of oxidation numbers of all atoms present in a neutral compound is zero. Oxidation No. of N + 3(Oxidation No. of H )...

All Students Notes

Search This Blog