CBSE question bank for class X

 CBSE question bank for class X 

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 ╭─❀⊰╯✍️ सामान्य विज्ञान #Part6

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1. क्रीम सेपरेटर में दूध में से वसा को किस कारण से अलग किया जा सकता हैं?

Ans➺ अपकेंद्री बल

2. फ्यूज तार किससे बनती हैं?

Ans➺ टिन और तांबे की की मिश्र धातु से

3. जो ऊर्जा पृथ्वी सतह के नीचे संचित ऊर्जा को काम में ला सकती हैं उसे क्या कहते हैं?

Ans➺ भूतापीय ऊर्जा

4. वाष्प इंजन में उबलते हुए जल का तापमान किस कारण से उच्च हो सकता हैं?

Ans➺ बॉयलर के अन्दर उच्च दाब होता हैं

5. एक बोतल को गर्दन से पकड़ा गया हैं और उधर्वाकार वृत्त में तेजी से घुमाया गया हैं तो बोतल के किस भाग के निकट बुलबुले एकत्र होंगे?

Ans➺ गर्दन के निकटतम

6. आवर्धक लेंस वास्तव में क्या होता हैं?

Ans➺ उत्तल लेंस

7. जल वाष्पीकृत नहीं होता हैं यदि?

Ans➺ आद्रर्ता 100% हो

8. प्रकाश के परिक्षेपण का अध्ययन करने के लिए किस उपकरण का प्रयोग किया जाता हैं?

Ans➺ स्पेक्ट्रोमीटर

9. फाउन्टेन-पेन किस सिद्धांत पर काम करता हैं?

Ans➺ केशिका क्रिया

10. फाइबर ऑप्टिकल किस सिद्धांत पर काम करते हैं?

Ans➺ पूर्ण आंतरिक परावर्तन

distinguishing features between overloading and short circuiting in domestic circuits

 Q. List two distinguishing features between overloading and short circuiting in domestic circuits. (CBSE 2014)

ANS-If too many electrical appliances of high power rating are switched on at the same time, they draw an extremely large current from the circuit causing overloading. 

Due to an extremely large current flowing through the circuit, the copper wire of the household wiring gets heated to a very high temperature and a fire may start. 

Short-circuiting: The touching of naked live wire and neutral wire directly causes short circuiting. In this case, the resistance of the circuit so formed is very small, thus a large amount of current flows through the circuit and heats the wires to a high temperature and a fire may start

Overloading of an electrical circuit

Q. What is meant by overloading of an electrical circuit? Explain two possible causes due to which overloading may occur in household circuit? Explain one precaution that should be taken to avoid the overloading of domestic electric circuit.

ANS- Overloading: The current flowing in domestic wiring at a particular time depends on the power ratings of the appliances being used. If too many electrical appliances of high power rating are switched on at the same time, they draw extremely large quantity of current from the circuit. This is known as the overloading of the circuit. 

Due to large current flowing through the wires of the household circuits, their copper wires get heated up to a very high temperature and can cause a fire.

SWAMY HANDBOOK 2023

To study fat in pure form and to detect into presence in given food sample

Aim: To study fat in pure form and to detect into presence in given food sample 

Material required: Test-tube, test-tube stand, test tube holder, burner etc.

Theory: Fats and oil are esters of long chain fatty acids and glycerol and thus also called glycerides. Fats contains saturated fatty acids while oil contain unsaturated fatty acids.

 Observation Table-

S.N.	EXPERIMENT	OBSERVATION	INFERENCE
1.	Spot test: put a small amount of sample on a filter paper and press with another filter paper	Translucent spot appears on filter paper	Fat is present
2.	Acrolein test: Take a few drops of sample in a test tube. Add few drops of potassium bisulphite to it and Heat.	Irritating smell appears due to the form of acrolein vapours.	Fat is present
3.	Solubility test: Take a small amount of sample in 3 test tubes. Add water, alcohol, and chloroform in 1, 2, 3 test tube respectively.	Sample does not dissolve in H2O but is soluble in alcohol on heating and soluble in chloroform.	Fat is present

 

Result: Fat is present in given sample of food.

To study carbohydrates in pure form of detect its presence in food

Aim: To study carbohydrates in pure form of detect its presence in food. 

Material required: Test-tube, test-tube stand, test tube holder, burner etc.

Theory: Carbohydrates are Polyhydroxy aldehydes or polyhydroxy ketones, their derivatives and the substance which yield them on hydrolysis carbohydrates are classified as sugars and non-sugars. Sugars like glucose, fructose and cane sugar are crystalline.

Among sugars, glucose, fructose, and lactose are reducing while sucrose is non reducing sugar.

 

S.N.	EXPERIMENT	OBSERVATION	INFERENCE
1.	Conc. H2SO4 test: Sample + Conc. H2SO4 + Heat	Charring with burnt sugar smell.	Carbohydrates present.
2.	Fehling solution test: Sample solution + 1 ml of Fehling A + 1 ml of Fehling B + D	Red ppt	Reducing sugar is present
3.	Tollen’s reagent: Aq. Solution of sample + 2 ml of Tollens reagent + D	Silver mirror is formed along the surface of test tube.	Reducing sugar is present
4.	Benedict’s Solution test: Aq solution of sample + Benedict’s reagent + Heat	Red ppt	Reducing sugar is present
5.	Iodine test: Sample Solution + few drops of iodine solution	Violet colour	Starch is present

 

Result : Carbohydrates is present in given sample of food.

To identify the functional group in the given organic compound

Aim : To identify the functional group in the given organic compound.

Material Required: Test-tube, test-tube stand, test tube holder, dropper, litmus solution, 2,4 DNP, dil. HCl, NaOH, sodium, nitroprusside, meta dinitro benzene.

Physical Properties:

State: liquid 

Color: colourless

Odor: Nail paint remover like smell 

Water solubility: soluble in water

Flammability: Burn with non-sooty flame (Aliphatic) 

Preliminary test :

S.N.	Experiment	Observation	Inference
1.	Litmus test: Organic compound + 2 drops of litmus solution.	No change	-COOH or phenolic   may present
2.	Organic compound + dil. HCl + NaOH	No ppt or oily layer	-NH2 group is absent.
3.	Organic compound + 2 ml of 2,4-DNP shake it and allow to stand	Orange-red ppt	Carbonyl group is present Aldehyde or ketonic group may be present

Confirmatory test :

S.N.	Experiment	Observation	Inference
1.	Organic compound + sodium nitroprusside + 2 – 3 drops of NaOH and shake.	Red color or wine- red color	>C=O group present
2.	Organic compound + Meta dinitrobenzene + NaOH	Violet  color which fades  on standing.	>C=O group present

 

Result: Given organic compound contains Ketonic grp. (>C=O)

To identify the functional group in the given organic compound

Aim : To identify the functional group in the given organic compound.

Material Required : Test tube, test tube stand, test tube holder, dropper, litmus (blue), NaHCO3, conc. H2SO4 , NH4OH, FeCl3

Physical Properties:

State: Solid 

Color: White 

Odor: phenolic

Water solubility: insoluble

Flammability: Burn with non-sooty flame (Aliphatic) 

Preliminary test :

S.N.	Experiment	Observation	Inference
1.	Litmus test: Organic compound + 2 drops of litmus solution.	Litmus solution turns from blue to red.	-COOH or phenolic (–OH) may be present
2.	Organic compound + NaHCO3 solution.	No effervescence.	-COOH group absent Phenolic (–OH) may be present.

Confirmatory test :

S.N.	Experiment	Observation	Inference
1.	FeCl3 Test: Organic compound + dil. FeCl3 solution	Green blue or violet coloration	Phenolic group is confirmed
2.	Phthalic test: Organic compound + phthalic acid + 2-3 drops H2SO4 + D then cool and add dil. NaOH	blue or red coloration	Phenolic group is confirmed

 

Result: The given organic comp. contains phenolic group.

           

To identify the functional group in the given organic compound

Aim : To identify the functional group in the given organic compound.  

Material Required : Test tube, test tube stand, test tube holder, dropper litmus (blue) solution, dil. HCl, NaOH, Na metal, dil. H2SO4, CH3COOH.

Physical Properties:

State: Liquid 

Color: Colourless

Odor: Spirit like smell 

Water solubility: soluble

Flammability: Burn with non-sooty flame (Aliphatic) 

Preliminary test :

S.N.	Experiment	Observation	Inference
1.	Litmus test: Organic compound + 2 drops of litmus solution.	No change	-COOH or – OH is absent
2.	Organic compound + dil. HCl + NaOH	No ppt or oily layer	-NH2 group is absent.
3.	Organic compound + Na metal	H2 gas evolves	-OH(alcohol) group     may be present

Confirmatory test :

S.N.	Experiment	Observation	Inference
1.	Cerric ammonium nitrate Test : Organic compound + cerric ammonium nitrate	Red color appears	-OH group is confirmed
2.	Ester Test : Organic compound + CH3COOH + Conc. H2SO4 (1 – 2 drops) + Heat.	Fruity smell of ester.	-OH group is confirmed

Result : The functional group present in the given organic compound is alcoholic group (- OH)

To identify the functional group in the given organic compound-carboxylic acid

Aim : To identify the functional group in the given organic compound.

Material Required : Test tube, test tube stand, test tube holder, dropper, litmus (blue), NaHCO3, conc. H2SO4 , NH4OH, FeCl3

Physical Properties:

State: Solid 

Colour: White

Odor: Vinegar Like

Flammability: Burn with non-sooty flame (Aliphatic) 

Preliminary test :

S.N.	Experiment	Observation	Inference
1.	Litmus test: Organic compound + 2 drops of litmus solution.	Litmus solution turns from blue to red.	-COOH or – OH may be present
2.	Organic compound + NaHCO3 solution.	Colourless, odorless gas with brisk effervescence.	-COOH group may be or – OH (phenol group present.

Confirmatory test :

S.N.	Experiment	Observation	Inference
1.	Ester test: Organic compound + C2H5OH + conc. H2SO4 + Heat	Fruity smell of ester	-COOH group is confirmed
2.	FeCl3 Test: Organic compound + dil. FeCl3 solution	Red color appears	-COOH group is confirmed

 

Result : The functional group present in the given organic compound is carboxylic acid