InterviewSolution
Saved Bookmarks
InterviewSolution
This section includes InterviewSolutions, each offering curated multiple-choice questions to sharpen your knowledge and support exam preparation. Choose a topic below to get started.
| 4502. |
Magnesium oxide is MgO, magnesium hydroxide is Mg(OH)_2 and magnesium sulphate is MgSO_4 What would be the formulae of barium oxide, barium hydroxide and barium sulphate if barium belongs to the same group, as magnesium ? |
|
Answer» Solution :As barium and MAGNESIUM belong to the same GROUP, barium has the same valency as magnesium. But the valency of magnesium is INDICATED to be two from the formulae of its compounds GIVEN in the question. Therefore, valency of barium is also two. The formulae of barium oxide, barium hydroxide and barium SULPHATE respectively are : `BaO, Ba(OH)_2 and Ba SO_4` |
|
| 4504. |
Magnesium is an element of group 2 of the periodic table. It forms compounds such as (i) magnesium oxide, MgO, (ii) magnesium hydroxide, Mg(OH)_2, (iii) magnesium sulphate, MgSO_4 and (iv) magnesium chloride, MgCl_2. Calcium is also an element of group 2. Write the formulae of calcium oxide, calcium hydroxide, calcium sulphate and calcium chloride. |
|
Answer» SOLUTION :The ELEMENTS of the same group FORM compounds of similar formulae. Thus (i) Calcium oxide CaO, (ii) calcium HYDROXIDE, `Ca(OH)_2`, (iii) calcium sulphate, `CaSO_4`, (iv) calcium chloride, `CaCl_2`. |
|
| 4505. |
Magnesium burns in air to form magnesium oxide. Do you know any other compound that is formedalong with magnesiumoxide ? |
| Answer» Solution :Yes, the other COMPOUND FORMED is MAGNESIUM NITRIDE. | |
| 4506. |
Magnesium belongs to |
|
Answer» GROUP 1 of the PERIODIC table |
|
| 4507. |
M xx V(ml) gives us |
|
Answer» Moles |
|
| 4508. |
M is an element which is out of Cu,Fe,Al,Na. It shows the following properties: (i) One of its ore is rich in M_2O_3. (ii) M_2O_3 is not affected by water. (iii) It corrodes easily. (iv) It forms two chlorides MCl_2 and MCl_3. Identify 'M' |
|
Answer» Solution :As the metal M FORMS oxide `M_2O_3` it is trivalent. Out of the metals listed, only FE and AL are trivalent. `M_2O_3` is not AFFECTED by water, so M can be out of Fe or Al. Fe and Al both corrode easily. Out of Al and Fe, only Fe can be form DIVALENT chloride, so the element M is Fe. |
|
| 4509. |
Lustre of metal is attributed to |
|
Answer» loosely bond ELECTRONS present in the valence shell of the METAL atoms |
|
| 4510. |
Lower hydrocarbons are………………state at room temperature. |
|
Answer» solid |
|
| 4511. |
Which carboxylic acid is present in the following :- (a) Tamarind (b) Nettle sting (c) Curd (d) Tomato |
| Answer» | |
| 4512. |
Loss of electron is called |
|
Answer» Reduction |
|
| 4513. |
Looking at its resemblance to alkali metals and the halogen family, try to assign hydrogen a correct position in Mendeleev's Periodic Table. To which group and period should hydrogen be assigned? |
| Answer» Solution :Hydrogen can be PLACED in both alkali metals eand halogen GROUP and period can.t DECIDED PROPERLY. This is in FACT, one of the limitations of Mendeleev.s Periodic Table. | |
| 4514. |
Look at the group 1 of the modern periodic table and name the elements present in it. ? |
| Answer» Solution :The names of the ELEMENTS present in group 1 are : HYDROGEN (H) , lithium (Li, Sodium (Na),potassium (K), rubidium (RB), CESIUM (CS) and francium (FR). | |
| 4515. |
Look at the following pictures. Label them as dilute and concentrated solution and justify your answer. |
| Answer» Solution :In the above picture, FIRST tea cup is more concentrated and first beaker is more concentrated `CuSO_4` solution. REASON is the COLOUR INTENSITY is more in concentrated solution. | |
| 4516. |
Look at the figure given below and answer the following questions Write the chemical equation involved in this process. |
| Answer» Solution :`CU(s)+O_(2)(G)UNDERSET("HEAT")(to)underset("Copper OXIDE")(2CuO(s))` | |
| 4517. |
Look at the figure given below and answer the following questions State the colour of the reactant and the product of the chemical reaction. |
|
Answer» SOLUTION :Colour of REACTANT : REDDISH brown Colour of product : BLACK |
|
| 4518. |
Look at the figure given below and answer the following questions Can we convert the product obtained back to reactant ? Write the reaction involved. |
|
Answer» Solution :On PASSING `H_(2)` gas over hot `CuO`, the REACTION can be REVERSED `CuO(s)+H_(2)(g)overset("HEAT")(to)Cu(s)+H_(2)O` |
|
| 4519. |
Look at the figure and answer the following questions: (a) What change wouldyou observe in the calcium hydroxide solution taken in tube B? (b) Write the reaction involved in A and B respectively. (c ) If ethanol is given instead of ethanoic acid, would you expect the same change? (d) How can a solution of lime water be prepared in the laboratory? |
|
Answer» Solution :(a) It will turn milky. (b) `CH_(3)COOH+NaHCO_(3) to CH_(3)COONa+H_(2)O+CO_(2)` (in A) `Ca(OH)_(2)+CO_(2) to CaCO_(3)+H_(2)O` (in B) With excess `CO_(2)`, milkiness disappears. (c ) As `C_(2)H_(5)OH and NaHCO_(3)` do not react, a similar change is not expected `C_(2)H_(5)OH+NaHCO_(3) to` No change (d) The lime water is prepared by dissolving calcium oxide in water and decanting the supernatant liquid. |
|
| 4520. |
Look at group 1 of the Modern Periodic Table, and name the elements present in it. |
| Answer» Solution :The elements in group 1 are: HYDROGEN (H). Lithium (LI), Sodium (Na), Potassium (K), RUBIDIUM (Rb). Cesium (Cs). and Francium (Fr). | |
| 4521. |
Locate the position in the periodic table of the following elements on the basis of their properties: a] An element is an inert gas with atomic number 10. b] An element is tetravalent and a basic element of organic chemistryc] A soft metal stored under kerosene that can be cut with knife. |
|
Answer» Solution :a) Since the ELEMENT is an inert gas, its group number is 18. Since its ATOMIC number is 10, it is placed in period 2,below helium. b] Since the element is tetravalent, it is placed in group 14. It is a basic element of organic chemistry: means it has to be carbon which is placed in the SECOND period. c] The element is sodium which is placed in the 1st group and the 3rd period. |
|
| 4522. |
Little litmus is placed in the cathode and the anode compartments of Hoffmann's voltameter containing acidulated water and then electrolysis is carried out. What do you observe and why ? |
| Answer» Solution :If blue litmus is added to the EATER in Hoffmann's voltameter, the colour of limtus is not changed in cathode compartment since the solution remains alkaline due to increase in `OH^(-)` IONS in the solution due to the discharge of `H^(+)` ions in the solution due to the discharge of `H^(+)` ions at the cathode to GIVE `H_(2)` gas. But blue litmus changes to red in the anode compartment since the `OH^(-)` ions get discharged at anode and the solution becomes rich in `H^(+)` ions. THUS, after ELECTROLYSIS, in cathode compartment, the solution is blue and in anode compartment it is red. | |
| 4523. |
Lithium, sodium, potassium are all metals that react with water to liberate hydrogen gas. Is there any similarity in the atoms of these elements ? |
|
Answer» Solution :Lithium, sodium and potassium are alkali metals which REACT with water to FORM METAL hydroxides with the release of HYDROGEN gas. `2M+2H_(2)Oto2MOH+H_(2)` Where, M = Li, Na and K All these metals have one electron in their respective valence SHELLS. |
|
| 4524. |
Lithium, sodium and potassium form a Dobereiner's triad. The atomic masses of lithium and potassium are 7 and 39 respectively. Predict the atomic mass of sodium. |
| Answer» SOLUTION :ATOMIC MASS of NA = `(7+39)/2=46/2=23` | |
| 4525. |
Lithium, sodium and ......... are the members of Dobereiner's triad. |
| Answer» SOLUTION :POTASSIUM | |
| 4526. |
Lithium, Potassium and Sodium are elementsforming Dobereiner's triad . |
| Answer» Solution :False . LITHIUM , SODIUM and Potassium are elementsforming Dobereiner . STRIAD. | |
| 4527. |
Lithium, Magnesium , Sodium , Potassium |
| Answer» SOLUTION :MAGNESIUM : It belongs to group II A (group 2), WHEREAS others belong to group I A (group 1). | |
| 4528. |
Lithium is the first metal of group 1. Name the second and third metals of this group. |
| Answer» SOLUTION :SODIUM (NA) and POTASSIUM (K) | |
| 4529. |
Lithium is more metallic than beryllium. Give reason. |
|
Answer» Solution :In lithium the valence electron (in L-shell) is ATTRACTED by three protons of the nucleus, whereas in beryllium the valence electrons PRESENT in L-shell are attracted by four protons in its nucleus. THEREFORE, • It is easier to remove a valence electron from the lithium atom than to remove an electron from the valence shell of a beryllium atom. • Since the metallic character of an element depends on the EASE with which an electron can be removed from its valence shell, lithium is more metallic than beryllium. |
|
| 4530. |
Lithium is an alkali metal with atomic number = 3 and number of valence electrons = 1. The formula of the hydride of lithium is LiH. Boron and carbon are placed in group 13 and 14 respectively with valence electrons 3 and 4. Write the formulae of the hydrides of boron and carbon giving a reason for your answer. |
| Answer» Solution :FORMULA for a HYDRIDE of BORON is `BH_3` and hydride of carbon is `CH_4` Since boron has 3 valence electrons and hydrogen has one, their COMPOUND has the formula BH, Since carbon has 4 valence electrons its compound with hydrogen has the formula `CH_4` | |
| 4531. |
Lithium, Beryllium, Boron, Chlorine |
| Answer» Solution :Chlorine: It BELONGS to the third PERIOD WHILEOTHERS are second period ELEMENTS. | |
| 4532. |
Lithium batteries are very expensive. Explain why they are still preferred |
|
Answer» SOLUTION :(i) Properties of lithium exploited in the battery (ii) WORKING principle of electrochemical cell. (III) Comparison of the OXIDATION potential of lithium with other metals. (iv) Relation between the oxidation potential of the metal used in the electrode and cell emf. (v) Comparison of DENSITY of lithium with other metals having relatively higher oxidation potential. (vi) Comparison of oxidation potential to density ratio of lithium to that of other metals (vii) Area of application of lithium battery |
|
| 4533. |
List two tests for experimentally distinguishing between an alcohol and a carboxylic acid and describe how these tests are performed. |
|
Answer» Solution :(i) We can distinguish between an alcohol and a carboxylic acid on the BASIS of their reaction with sodium carbonate and sodium hydrogen arbonate Carboxylic acids reacts with sodium carbonate and sodium hydrogen carbonate to evolve `CO_(2)` gas that turns lime water milky. Alcohol, on the other hand, do not REACT with sodium carbonate and sodium hydrogen carbonate. (II) Alcohol reacts with sodium metal to produce hydrogen gas with RAPID effervescence. On the other hand, carboxylic acid does not show this type of CHEMICAL reaction with sodium metal. |
|
| 4534. |
List two tests for experimentally distinguishing between an alcohol and a carboxylic acid and describe howthese tests are performed . |
|
Answer» Solution :(i) Test with `NaHCO_(3)` solution in water. On adding carboxylic ACID to baking soda, c arbon DIOXIDE is LIBERATED with brisk effervescence. On adding a solution of banking soda to alcohol, no brisk effervescence occurs. (ii) Test with blue LITMUS solution. Carboxylic acid turns blue litmus red. There is no change in colour when a blue litmus solution is added to alcohol. |
|
| 4535. |
List two reasons for carbon forming a large number of compounds. Name the type of bonding found in most of its compounds. Why does carbon form compounds mainly by this kind of bonding. Give reason why the carbon compounds: (i) Generally have low melting and boiling points. (ii) Do not conduct electricity in molten state. |
|
Answer» Solution :Two of the main REASONS because of which CARBON forms a large number of organic compounds are: 1. Tetravalent nature of carbon 2. Greater C-C bond strength Carbon compound are formed by covalent bonds. (i) Carbon compounds have low melting and boiling point because these compounds are bonded with covalent bond and ALSO forces of attraction between these molecules are not very strong. (ii) Because carbon compounds are covalent in nature, they are bad conductors of electricity, they LACK free ELECTRONS. |
|
| 4536. |
List two functions of finger like projections present in the small intestine. |
| Answer» SOLUTION :The inner lining of the small intestine has numerous finger-like projections called villi which increases the surface area of absorption of digested food. The villi are richly supplied with blood VESSELS which TRANSPORT the abosrobed food to each and every cell of the body, where it is utilised for obtaining energy, building up new tissues and the REPAIR of the old ONES. | |
| 4537. |
List two characteristic features of carbon which when put together give rise to a number of carbon compounds. |
| Answer» SOLUTION :The TWO FEATURES are : CATENATION and TETRAVALENCY. | |
| 4538. |
List two differences between saturated and unsaturated hydrocarbons. |
| Answer» Solution :`{:("Saturated Hydrocarbon","Unsaturated Hydrocarbon"),(1. "They have only single","They have atleast one"),( "bond between the carbon","double or triple bond"),("atoms","between the carbon"),(,"atoms"),(2."Gives a clean flame on","Gives yellow flame with"),("BURNING","a lot of black SMOKE on"),(,"burning"),(3."They under go","They UNDERGO addition"),("substitution REACTION","reaction"):}` | |
| 4539. |
List three properties of sodium by which it differs from the general physical properties of most metals. |
|
Answer» SOLUTION :Three properties of SODIUM are : (i) Sodium is so SOFT that it can be CUT with a knife. (ii) It has low density (iii) It has low MELTING point. |
|
| 4540. |
List three factors responsible for the wind . State three limitations in harnessing wind energy. |
|
Answer» SOLUTION :Three factors responsible for wind i) Uneven heating of earth.s surface. ii) Rotation of the earth. iii) Local condition -change in pressure, temperature. Three limitations. i) Can be used where wind BLOWS for a greater part of the YEAR. ii) Wind speed should be higher than 15 km/hr. iii) Establishment is EXPENSIVE and requires large AREA. |
|
| 4541. |
List the three kinds of blood vessels of human circulatory system and write their functions in tabular form. |
|
Answer» Solution :i) ARTERIES. They CARRY blood away from the heart to various organs of the body. ii) Veins : They collect the blood from different ORGAN and bring it back to the heart. iii) Capillaries : Exchanges of material between the blood and surrounding cells takes place across the thin WALLS of capillaries. |
|
| 4542. |
List the organic acid present in the following objects. a) Citrus fruits (Lemon, orange) b) Sting of bee and ants. c) Rancid butter d) Tamarind, grapes, apples e) Gastric juice f)Vinegar g) Fats h) Urine i) Sour milk, curd |
|
Answer» Solution :a) Citric ACID B) Formic acid c) Butryic acid d) Tartaric acid e) Hydrochloric acid t) Acetic acid g) STEARIC acid h) URIC acid i) LACTIC acid |
|
| 4543. |
List the four characteristics of a good source of energy. Name any two sources of energy which are dependent on solar energy. |
|
Answer» Solution :Characteristics of good source of ENERGY are : Provide large amount of CONTINUOUS supply of energy per unit mass or volume. Cheap and easily available. Safe to store and easy to transport. Economical and should not pollute the environment. The TWO major TYPES of SOLAR energy that make it to Earth are heat and light. |
|
| 4544. |
List the disadvantages of using fosil fuels. |
|
Answer» Solution :Fossil fuels are formcd ROM carbon and biomass which contains hydrogen, carbon, nitrogen and sulphur. When these are BURNT, the products are oxides of earbon, WATER, oxides of nitrogen and oxides of sulphur. Oxides of nitrogen. oxides of sulphur and carhon monoxide are poisonous at high concentration. They may lcad to acid rain. Carbon dioxide is a greenhouse gas. When its concentration in the atmosphere INCREASES continuously, leads to intcnce global WARMING. |
|
| 4545. |
List the advantages of 'reduce' and 'reuse' to save environment. Advantages of reduce and reuse to save environment: |
|
Answer» Solution :REDUCE :By the PRACTICE of .Reduce., we can save (a) Electricity (b) Water (C) Food (d) Natural resources. Reuse : By the practice of .Reuse. (a) ENVIRONMENT poilution can be controlled (b) Materials are available for immediate use (c) Energy can be SAVED (d) Use of raw materials can be minimised. |
|
| 4546. |
List the advantages of reduce and reuse' to save environment . |
|
Answer» Solution :Advantages of reduce and REUSE to save environment : Reduce : By the PRACTICE of .Reduce., we can save (a) Electricity (B) Water (c) Food (d) Natural resources Reuse : By the practice of .Reuse. (a) Environment pollution can be controlled (b) Materials are available for immediate use (c) Energy can be saved (d) Use of raw materials can be minimised. (CONSIDER other related ans. also). |
|
| 4547. |
List out the examples for hygroscopic substances. |
|
Answer» SOLUTION : 1. Conc.Sulphuric acid `(H_2 SO_2)`. 2. PHOSPHORUS Pentoxide `(P_2 O_5)`. 3. Quick lime (CaO). 4. Silica gel `(SiO_2)`. 5. ANHYDROUS calcium chloride `(CaCl_2).` |
|
| 4548. |
List out any two problems that arise due to use of detergents instead of soaps. |
|
Answer» SOLUTION :a] They are non-biodegradable, hence CAUSE POLLUTION. b] They MAY LEAD to blooming of algae on the surface of water leading to .Eutrophication.. |
|
| 4549. |
List in a tabular form, the changes in colour observed and the name of the compound formed when silver, copper and iron are said to be corroded. |
Answer» SOLUTION :The INFORMATION in the TABULAR FORM is GIVEN as under :
|
|
| 4550. |
List in tabular form tow differences between an acid and a base based on their chemical properties. |
| Answer» SOLUTION :`{:("Acids","Bases"),(1.H^+ "ions are released in AQUEOUS solution",1.OH^(-) "ions are released in aqueous solution" ),("2. Reacts with METAL carbonates to liberate "CO_2"gas.","2. No reaction takes PLACE with metal carbonates"):}` | |