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This section includes 7 InterviewSolutions, each offering curated multiple-choice questions to sharpen your Current Affairs knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
The salt which help in the formation of soap is : (A) Calcium sulphate (B) Sodium sulphate Sodium chloride (D) Calcium chloride |
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Answer» hey MATE sodium chloride is the correct ANSWEREXPLANATION:MAY it is HELPFUL for yoube Brainiest!!!!!please mark as brainiest answer |
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| 2. |
On the basis of study of saponification reactions, a group of students noted down the following comments in their notebooks : I. The nature of the reaction mixture is basic. II. In saponification reactions, heat is evolved. III. Saponification reaction is not a neutralization reaction. IV. Soap is nothing but a salt of fatty acids. Select the correct comments : (A) I, II and In (B) I, II and IV (C) 11, HI and IV (D) III, IV and I |
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Answer» hey MATE ...options are not accurate...can you PLEASE CHECK it |
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| 3. |
When a student performs saponification, he observes that the container becomes hot. This indicates that saponification reaction is : (A) Endothermic (B) Exothermic (C) Both (A) and (B) (D) Neither (A) nor (B) |
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Answer» udent,◆ Answer -(B) Exothermic● Explaination -Soaps are SALTS of higher fatty acids with sodium/potassium hydroxide.Saponification is a reaction involving FORMATION of soaps.During this reaction, heat is evolved into the surroundings.Due to EXTRA heat evolved into surroundings, the container becomes hot.Hence, saponification is an exothermic reaction.Hope I was USEFUL. Best luck dear... |
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| 4. |
Sodium oleate is the chemical name of the soap formed from : (A) Olive oil and sodium hydroxide (B) Palm oil and sodium hydroxide (C) Olive oil and potassium hydroxide (D) Palm oil and potassium hydroxide |
| Answer» | |
| 5. |
Soap micelles in water will not come together to precipitate because of: (A) Ion-ion attraction between micelles (B) Ion-ion repulsion between micelles (C) Electro negativity of micelles (D) Electro positivity of micelles |
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Answer» tudent,◆ ANSWER -(B) Ion-ion repulsion between micelles● Explanation -MICELLE is aggregate of soap MOLECULES in the solution.When soaps DISSOLVE in water, hydrophobic end of soap molecules concentrate AROUND the dirt and form micelles. As similar ions are present near each other, they repel each other and don't precipitate. Instead they form a colloidal solution.Hope I am useful... |
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| 6. |
The chemicals used for the preparation of toilet soap are : (A) Fat and sodium hydroxide (B) Fat and potassium hydroxide (C) Water and sodium hydroxide (D) Water and potassium hydrogen |
| Answer» | |
| 7. |
On mixing acetic acid with water : (A) A suspension is formed (B) A colloidal solution is formed (C) A homogeneous solution is formed (D) A heterogenous solution is formed. |
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Answer» CH3COO+H3O is FORMED which is normally CALLED vinegarAccording to me , C) homogenous mixture is formed |
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| 8. |
Deepa was asked to identify bottles of acetic acid from a shelf where a number of other labelled bottles were placed. She reads the labels as : (i) Vinegar (ii) Formic acid (iii) Ethanoic acid (iv) Ethanol. Correct identification would be : (A) i, ii (B) 1, iv (C) ii, iv (D) i, iii |
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| 9. |
Ethanoic acid was added to washing soda solution and the gas evolved was tested with a burning splinter. Which of the following four observations is correct? (A) The gas burns with a pop sound and the flame gets extinguished. (B) The gas does not burn but the splinter burns with a pop sound. (C) The flame extinguishes and the gas does not burn. (D) The gas burns with a blue flame and the splinter burns brightly. |
| Answer» TION:(C) The FLAME extinguishes and the gas does not burn.HOPE IT HELPS YOU!!! | |
| 10. |
Four students performed an experiment of acetic acid with sodium carbonate (I), the sodium hydroxide (II), sodium bicarbonate (III) and sodium chloride (IV) separately. Each one brought burning candle near the mouth of the test-tube. The candle would not be extinguished near the mouth of the test-tubes :(A) i and ii (B) i and iii (C) ii and iii (D) ii and iv |
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Answer» Explanation:If (a+B)/X = (c+d)/nHere a+b = XAnd N= X + 4a,b,c and d are continuous numbers.This FORMULA is created by me(Tanishq Gupta).This formula is known as E-ON LAWSMy QUESTION is give a NUMERICAL example of 4 digit number like 1003,1004,1005,1006. |
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| 11. |
Acetic acid is : (A) Soluble only in boiling water (B) Soluble in water at room temperature (C) Partially soluble in water (D) Insoluble in water. |
| Answer» ACETIC acid is extremely soluble in water, but most of the dissolved COMPOUND remains as molecules, rendering it a weak ELECTROLYTE. Acetic acid is extremely soluble in water, but only a small fraction is dissociated into IONS, rendering it a weak electrolyte. | |
| 12. |
About 2 ml of acetic acid was taken in each of the three test-tubes P, Q and R and 5 m], 10 ml and 15 ml of distilled water were added to them, respectively. Instantaneously a clear solution is observed in the test-tubes: (A) P and Q only (B) Q and R only (C) R and P only (D) P, Q and R |
| Answer» TION:............................ | |
| 13. |
Among the two test-tubes I and II, one contains acetic acid and another contains water. Which of the properties of acetic acid can be used to identify acetic acid from it ? I. Colour change with universal indicator II. Reaction with NaHCO3 III. Colour of the solution IV. Transparent nature (A) l and II (B) 11 and III (C) III and IV (D) I and IV |
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| 14. |
Select the correct observation about dilute solution of acetic acid. (A) It smells like rotten egg and turns blue litmus red. (B) It smells like Vinegar and turns red litmus blue. (C) It smells like rotten egg and turns red litmus blue. (D) It smells like Vinegar and turns blue litmus red. |
| Answer» AEXPLANATION: | |
| 15. |
In an experiment to study the properties of acetic acid a student takes about 2 ml of acetic acid in a dry test-tube. He adds about 2 ml of water to it and shakes the test-tube well. He is likely to observe that: (A) Acetic acid dissolves readily in water (B) The solution becomes light orange (C) Water floats over the surface of acetic acid (D) Acetic acid floats over the surface of water |
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Answer» according to me answer of your question is part B the solution BECOME light ORANGE |
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| 16. |
A student takes about 2 ml ethanoic acid in a dry test tube and adds a pinch of sodium hydrogen carbonate to it. He reports the following observations : I. Immediately a colourless and odorless gas evolves with a brisk effervescence. II. The gas turns lime water milky when passed through it. III. The gas burns with an explosion when a burning splinter is brought near it‘ IV. The gas extinguishes the burning splinter that is brought near it. The correct observations are : (A) 1, II and III (B) It, 111 and IV (C) III, IV and I (D) I, II and IV |
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| 17. |
When you add about 2 ml of acetic acid to a test-tube containing an equal amount of distilled water and leave the test-tube to settle after shaking its contents, what will you observe in the test-tube after about 5 minutes? (A) A white precipitate settling at its bottom (B) A clear colorless solution (C) A layer of water over the layer of acetic acid (D) A layer of acetic acid over the layer of water |
| Answer» EXPLANATION:OK BYE | |
| 18. |
A student adds a few drops of ethanoic acid to test tubes X, Y and Z containing aqueous solutions of sodium chloride, sodium hydroxide and sodium carbonate, respectively. If he now brings a burning splinter near the mouth of the test-tubes immediately after adding ethanoic acid in each one of them, in which of the test tube or test-tubes the flame will be extinguished ? (A) X and Y (B) Y and Z (C) XandZ (D) onlyZ |
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Answer» (D)only ZExplanation:Only TEST tube Z wlll be EXTINGUISHED. The flame will be extinguished when test tube Z is brought near a BURNING splinter due to evolution of carbon DIOXIDE gas, which does not support combustion.HOPE IT HELPS YOU!!! |
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| 19. |
An organic compound ’A' with molecular formula C2H60 gives compound 'B’ on oxidation with alkaline KMnO4. ’A’ an heating with conc. H2S04 gives ‘C' which on reaction with phosphoric acid and water gives back ‘A’. Compound ’C’ gives addition product with Br2 and H2. Identify A, B, C and write chemical equations involved. |
| Answer» UND A is ethanol.C2H6O is isomer of ethanol.2.Compound B is ethanonic acid. it FORMS due to oxidation.3. compound C is ethene. sulphuric acid is a DEHYDRATING agent. the product is CH2 double BOND CH2 + water(H2O) | |
| 20. |
A student adds 2 ml of acetic acid to a test-tube containing 2 ml of distilled water. He then shakes the test-tube well and leaves it to settle for some time. After about 5 minutes he observes that in the test tube there is : (A) A clear transparent colourless solution (B) A clear transparent pink solution (C) A precipitate settling at the bottom of the test tube (D) A layer of water over the layer of acetic acid. |
| Answer» ANSWER for the QUESTION | |
| 21. |
In an experiment to study the properties of ethanoic acid, a student takes about 3 ml of ethanoic acid in a dry test-tube. He adds an equal amount of distilled water to it and shakes the test-tube well. After some time he is likely to observe that : (A) a colloid is formed in the test-tube. (B) the ethanoic acid dissolves readily in water. (C) the solution becomes light orange. (D) water floats over the surface of ethanoic acid. |
| Answer» | |
| 22. |
Ethanol, commonly called as ’alcohol’ is an excellent solvent, it used in medicines and is an important chemical compound involved in synthesis of many chemical compounds. However inspite of its benefits to man, its impact on social behaviour has always been questioned. Media has often shown abnormal behaviour of people while drunk. It is considered as a curse in the lives of those who are addicted to alcohol. ’Alcoholic' people are not only lowering their metabolism and affecting centrol nervous system, they are also a threat to the lives of others. Anger and rude behaviour are some of its ill effects. |
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Answer» n is incomplete. Here is the complete question taken from CLASS X science book. 1)Comment on the statement – ‘Should production of alcohol should be banned’, give three valid reasons to justify. 2)As a student what initiative would you take in the common concern of ‘Save Life, Do not Drink’. Give two suggestions.In a favour of negative response:--> it is widely used industrial solvent .---> it is widely used in medicines like tincture iodine , cough.---> it is also used as antiseptic to sterilize wounds and syringes syrups. ln favour of positive response :--->Drunken driving leads to increased road accidents.--->The drinking of adulterated alcohol containing methyl alcohol causes SEVERE poisoning leading to blindness an even death.Two suggestions :--> Create awareness among public about side EFFECTS of alcohol by conducting rallies, skits etc.--->Conducting ESSAY writings, drawing competitions in schools and exhibit them in school.---> Organizing an exhibition on the charts and drawings done by students . |
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| 23. |
Soaps are sodium or potassium salts of higher fatty acids. Fatty acids are carboxylic acids containing 12 or more carbon atoms. Detergents are sodium or potassium salts of sulphonic acids. They have SO3Na group and can even work with hard water. Soap forms an insoluble substance called residue with hard water. This is due to its reaction with the calcium and magnesium salts which cause the hardness of water. Thus, a larger amount of soap needs to be used. (i) What is saponification ? (ii) Which group is present in soaps ? (iii) What is micelle ? (iv) How does micelles dissolve dirt and greese ? (v) Which type of detergents are non-biodegradable ? |
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Answer» and NA GROUP is present in soapii) Michelle is an AGGREGATE of molecules in a COLLODIAL solution , such as those are formed by detergents |
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| 24. |
Two compounds ’A’ and ’B’ have the same molecular formula C3H6O2. One of them reacts with sodium metal and NaHCO3 to liberate H2 gas and a gas ’C', respectively. ’C' turns lime water milky. The other compound does not react with either Na metal or NaHCO3 but undergoes saponification to give sodium salt of a carboxylic acid and wood spirit, 'D’. Identify A, B, C and D. |
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Answer» tion:5x54x6yx.y6x4624..y55555555x54x6yx.y6x4624..y5555555 |
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| 25. |
(a) Write the name of the following compounds CH3CH2COOH,C6H6 (b) What is a homologous series .7 Write the formula of functional group of ketone and aldehyde. (c) What will happen if ethanol reacts with ethanoic acid, in the presence of an acid ? Name the reactions. Write the chemical equation for this reaction. |
| Answer» CH3CH2COOH:- propanoic acid. C6H6:-benzene.Homologous SERIES is a series of compoundhaving different chemical properties and Same functional GROUP. plzzz mark me brainliest... plzz I need plzzz really yrrrr | |
| 26. |
(a) Complete the following equations : Cummso (1) CH3CHZOH 11—" (ii) CHSCOOH + KHCO3 s”"”“"‘ > (iii) CH4 + Clz —> (b) Write the name of the following : (i) CHECHZCOOH, (ii) CHSCHZCHZBL (c) Draw the electron dot structure of ethene (CZH4). |
| Answer» | |
| 27. |
(a) How will you bring about following reactions? Write the concerned chemical equations (i) Ethanol to Ethene (ii) Ethanol to Ethanoic acid (b) Give one example with chemical equation for the following reactions : (i) Substitution reaction (ii) Saponification reaction(iii) Combustion reaction |
| Answer» EXPLANATION:Don't KNOW | |
| 28. |
(a) Complete the following equations (i) nCHZ = CHZ —> .................(ii) CH 3—C002H + NaHCO3 —> ........ + ...... +. (b) What is the cause of hardness of water? Why soap do not form lather with hard water? Mention the disadvantage of cleaning clothes with soap in hard water ? |
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Answer» this is acid base reaction here CH3COOH is acid and NaHCO3 is base hence salt form. i.e. CH3COOH+NaHCO3----> CH3COONa +H20 +CO2Explanation:Half of this is a double displacement reaction. The reaction TAKES place in two steps. Step 1 CH₃COOH(aq) + NaHCO₃(s) → CH₃COONa + H₂CO₃(aq) This is a double displacement reaction because the Na trades partners with the H of CH₃COOH. Step 2 The carbonic acid formed in Step 1 DECOMPOSES into CO₂ and water. H₂CO₃(aq) → CO₂(g) + H₂O(l) This is a decomposition reaction, because one substance is converted into two different substances. OVERALL Reaction If you ADD the two equations together, the H₂CO₃ cancels out, and you get CH₃COOH(aq) + Na₂CO₃(s) → CH₃COONa(aq) + CO₂(g) + H₂O(l) |
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| 29. |
(a) "Covalent compounds have low melting and boiling points”. Justify this statement. (b) What is an ester P Describe an activity to form an ester in a school laboratory. |
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Answer» JustExplanation: |
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| 30. |
An organic compound ’X’ on heating with cone. H2S04 forms :1 compound ’Y' which on addition of one molecule of hydrogen in the presence of nickel forms a compound ’2'. One molecule of compound ’2' on combustion forms two molecules of CO2 and three molecules of H20. Identify giving reasons the compounds ’X', 'Y' and ’2'. Write the chemical equations for all the chemical reactions involved. |
| Answer» EXPLANATION:TQ | |
| 31. |
(a) Write the chemical names of CH3COCHl3, C2H5COOH. (b) What happens when acetic acid and ethanol reacts in presence of concentrated H2SO4 ? Write the reactions there in. |
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Answer» udent,◆ Answers -(a) Chemical NAMES -CH3-CO-CH3 = Propanone (aka ACETONE)C2H5-COOH = Propanoic acid (aka propionic acid)(B) When ACETIC acid and ethanol react in presence of conc.H2SO4, ethyl ethanoate is formed. This is called esterification. Water is formed as BYPRODUCT in this reaction. CH3COOH + CH3CH2OH --> CH3COOCH2CH3 + H2OThanks dear. Hope this helps you... |
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| 32. |
Complete the following reactions 2 (a) CHSCHZOH Alkaline 7 KM no. + H sat (b) 2Na + 2CH3CH20H —> ? + a.d (c) CHSCOH + CH3CHZOH L |
| Answer» ESTION s ANSWER | |
| 33. |
An organic compound A is widely used as a preservative in pickles and has a molecular formula C2H402- This compound reacts with ethanol to form a sweet smelling compound B. (a) Identify the compound A. (b) Write the chemical equation for its reaction with ethanol. (c) Name the products formed. (d) Name the process involved in the reaction. (e) How can we get back the compound A from B. |
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Answer» I can't UNDERSTAND your QUESTIONS EXPLANATION:I can't understand your questions |
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| 34. |
An organic compound ’A’ of molecular formula C2H6O on oxidation with dilute alkaline KMnO4 solution gives an acid ’B' with the same number of carbon atoms. Compound ’A’ is often used for sterilization of skin by doctors. (a) Name the compounds ‘A’ and ’B’. (b) Write the chemical equation involved in the formation of ‘B' from ’A’. |
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Answer» riend,(a) Compounds -Compound A => Ethanol (CH3-CH2-OH)Compound B => Ethanoic acid (CH3-COOH)b) Reaction -Ethanol (compound A) on OXIDATION with strong oxidizing agent like alk.KMnO4 gives ethanoic acid (compound B). CH3-CH2-OH + 2[O] --> CH3-COOH + H2O* If weak oxidizing agent was USED, acetaldehyde will be obtained instead of acetic acid.CH3-CH2-OH + [O] --> CH3-CHO + H2OHope I helped you. Thanks for asking... |
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| 35. |
(a) Give a chemical test to distinguish between saturated and unsaturated hydrocarbons. (b) Name the products formed when ethanol burns in air. List two forms of energy that are liberated on burning ethanol. (c) Why is the reaction between methane and chlorine considered a substitution reaction ? |
| Answer» DONT KNOW can you HELP me in this QUESTION | |
| 36. |
How are the following products obtained from ethanol ? (a) Ethyl ethanoate (b) Sodium ethoxide. |
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Answer» tion:(i) ETHANOL reacts with ETHANOIC acid in the presence of an acid catalyst to give ethyl ethanoate. (ii) When ethanol reacts with sodium, sodium ETHOXIDE is produced ALONG with the liberation of HYDROGEN. 2CH3CH2OH+2Na → 2CH3CH2ONa...Hope it will help u..Thanks.. |
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| 37. |
Complete the following equations : (a) CH3COOC2H5 ---> NaOH (b) CH3COOH + NaHCO3 (c) CH4 + Cl2 ---> Sunlight |
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Answer» (a) CH₃COOC₂H₅+ NaOH → CH₃COONa + C₂H₅OH(Ethyl ACETATE when reacts with alkali NaOH, it forms Sodium Acetate and Ethanol)(b) CH₃COOH + NaOH → CH₃COONa + H₂O(Acetic acid reacts with Sodium Hydroxide to PRODUCE Sodium Acetate and Water)(c) CH₄ + Cl₂ + Sunlight → CH₃Cl + HCl(When Methane and Chlorine is exposed to ultraviolet light (sunlight) a substitution reaction OCCURS and the product is Chloromethane, the process CONTINUES TILL all the Hydrogens are replaced by Chlorine) |
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| 38. |
Write the chemical equations for the following chemical reactions and name the carbonic compound obtained. (i) Reaction of acidified potassium dichromate solution with ethanol on heating. (ii) Reaction of sodium metal with ethanol. (iii) Reaction of concentrated sulphuric acid with ethanol at 443 K. |
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Answer» tudents,(i) Reaction of acidified potassium dichromate solution with ethanol on heating -CH3CH2OH + 2[O] → CH3COOH + H2OCarbonic compound - Ethanoic acid(ii) Reaction of sodium metal with ethanol -Na + CH3CH2OH → CH3CH2ONa + ½H2Carbonic compound - Sodium ETHOXIDE(III) Reaction of concentrated sulphuric acid with ethanol at 443 K -CH3CH2OH → CH2=CH2 + H2OCarbonic compound - EtheneHope I was useful... |
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| 39. |
Draw the electron dot structure of ethyne. A mixture of ethyne and oxygen is burnt for welding. In your opinion, why cannot we use a mixture of ethyne and air for this purpose. |
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Answer» ..................... |
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| 40. |
With the help of an example, explain the process of hydrogenation. Mention the essential conditions for the reaction and state the change in physical property with the formation of the product. |
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Answer» The PROCESS when hydrogen is added to an UNSATURATED hydrocarbon to form a saturated hydrocarbon is called hydrogenation.GROUNDNUT oil is a vegetable oil which is unsaturated and in LIQUID state. It contains DOUBLE bonds (C=C). On hydrogenation, the groundnut oil produces vanaspati ghee which is solid at room temperature.(The Reaction is attached in the figure)The essential conditions for the reactions are presence of unsaturated hydrocarbon and presence of a catalyst like Pt, Pd, Rh, Ni.The change in the physical properties observed are(i) Change of unsaturated hydrocarbon in liquid state to saturated hydrocarbon in solid state(ii) Increase in melting point or boiling point. |
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| 42. |
When we take 1 ml ethanol and 1 ml ethanoic acid along with a few drops of concentrated sulphuric acid in a test. tube a sweet smelling substance is formed. Name the compound and give the balanced chemical equation for the reaction. What do we call the reverse reaction to give back alcohol and carboxylic acid which is used in the preparation of soap ? |
| Answer» DONT KNOW PLEASE can you HELP me | |
| 43. |
The structural formula of an ester is : Sodium hydrogen H O H H H Hl H l | l l“‘i‘c‘o‘i‘i‘i‘i‘” II II II 11 II Write the structural formula of the acid and the alcohol from which it might be prepared. Name the process of formation of ester. |
| Answer» TION:QUESTION is IMPROPER MAKE it CLEAR | |
| 44. |
Write chemical equation of the reaction of ethanoic acid with the following : (a) Sodium (b) Sodium hydroxide (c) Ethanol. Write the name of one main product of each reaction |
| Answer» PLZZZ FOLLOW me BRO... | |
| 45. |
(a)What is a catalyst ? Write the chemical equation to represent the hydrogenation of ethene. (b) Which of the following compounds belong to the same homologous series ? C2H6 C2H6O2, C2H6O, C4HI0 |
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Answer» A catalyst is a SUBSTANCE that does not takes part in a checmical reaction but increase or DECREASE the RATE of the CHEMICAL reaction EXPLANATION: |
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| 46. |
In a monohybrid cross between tall pea plants (TT) and short pea plants (tt) a scientist obtained only tall pea plants (Tt) in the F 1 generation. However, on selfing the F1 generation pea plants, he obtained both tall and short plants in F2 generation. On the basis of above observations with other angiosperms also, can the scientist arrive at a law ? If yes, explain the law. If not, give justification for your answer. |
| Answer» YES law of DOMINANCE or law of segregationor law of inheritanceThe trait of TALLNESS is dominant according to it,the characteristics of an organism are DETERMINED by INTERNAL factors which occurs in Pairs | |
| 47. |
What happens when a Planaria gets cut into two pieces? |
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Answer» when a PLANARIA cut into two pieces then it reproduces into two NEW planaria from that cut pieces because of having SIMPLE tissues.hope this HELPS you |
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| 48. |
What is meant by scattering of light ? The sky appears blue and the sun appears reddish at sunrise and sunset. Explain these phenomena with reason |
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Answer» ttering of LIGHT - Phenomenon of spreading of light (DIFFUSED, reflection) by minute particles in a medium. (ii) The sky appears BLUE because of the blue color of SUNLIGHT scatter MUCH more strongly than the red colour by particles in atmosphere/ air due to its shorter wavelength. (iii) At sun-rise and sun-set most of the blue light and shorter wavelengths are scattered away by the particles in the atmosphere as the light from the sun near the horizon passes through thick layers of air and larger distance. The light that reaches us is of a longer wavelength (red colour) giving a reddish appearance.Read more on Sarthaks.com - https://www.sarthaks.com/168556/what-meant-scattering-light-the-sky-appears-blue-and-the-sun-appears-reddish-sunrise-sunset |
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| 49. |
How did Mendel interpret his result to show that traits may be dominant or recessive? Describe briefly. |
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Answer» tion:Mendel demonstrated that TRAITS can be either dominant or recessive through his monohybrid cross. He crossed true-breeding tall (TT) and dwarf (tt) PEA plants. ... From this experiment, Mendel CONCLUDED that the F1 tall plants were not true breeding; they were CARRYING traits of both SHORT height and tall height...Hope it will help u... |
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| 50. |
Name any two elements of group one and write their electronic configurations. What similarity do you observe in their electronic configurations 7 Write the formula of oxide of any of the aforesaid element. |
| Answer» HYDROGEN and LITHIUM E. CONFIGURATION is 1s^2 | |