8881 + Interview Questions in Chemistry in Class 10 Page 30 InterviewSolution

1451.	Write the name and molecular formula of an alkyne having four carbon atoms.
Answer» Solution :BUTYNE `(C_(4)H_(6))`.

Discussion

1452.	What type of oxides are formed, when non metals combine with oxygen?
Answer» Solution :Non-metals react with oxygen to form acidic oxides or NEUTRAL oxides. Carbon FORMS an acidic OXIDE `CO_2`, sulphur forms an acidic oxide `SO_2` and hydrogen forms a neutral oxide `H_2O`. Carbon monoxide (CO), NITROUS oxide `(N_2O)` and nitric oxide (NO) are also the examples of neutral oxides.

Discussion

1453.	When an atom occupies an interstitial site it is known as
Answer» INTERSTITIAL defect vacancy defect both a and b none of the above Answer :A

Discussion

1454.	Write one example of each of the following:(a) A metal and a non-metal which are liquids at room temperature. (b) A metal which is very soft and a non-metal which is very hard. (c) A metal which has very low melting point and a non-metal which has very high melting point.
Answer» Solution : (a) Mercury (a METAL) is a liquid at room TEMPERATURE.Bromine (a non-metal) is a liquid at room temperature. (b) Sodium (a metal) is very soft.Diamond (a FORM of CARBON) is very HARD. (c) Gallium has a very low melting point. Diamond (a non-metal) has a very high melting point.

Discussion

1455.	What are noble metals?
Answer» SOLUTION :Those metals that have least reactivity and do not REACT with AIR, water, acid and bases are referred to as noble metals. For EG: Gold, platinum.

Discussion

1456.	Which of the following elements react(s) whit acids to form salts (a salt) ?
Answer» Sulphur PHOSPHOROUS SODIUM SILICON ANSWER :C

Discussion

1457.	What is called rancidity ?
Answer» Solution :Rancidity : Oil and fat containing food when EXPOSED to AIR gets oxidised and it become RANCID due to which its taste and SMELL change. This reaction is called rancidity. Such food items are not suitable for CONSUMPTION.

Discussion

1458.	Valency of an element is determined by the number of electrons present in the first shell.
Answer» SOLUTION :False - It is DETERMINED by the NUMBER of electrons in the OUTERMOST shell.

Discussion

1459.	Which one of the following will be displaced from its salt solution by copper?
Answer» `Fe^(2+)` `AG^+` `ZN^(2+)` `AL^(2+)` SOLUTION :`Ag^+`

Discussion

1460.	Which of the following statements is false
Answer» Bohr's theory explains only the spectra of SINGLE ELECTRON specis The ENERGY of an electron remains constant during electronic TRANSITION The angular momentum of an electron is quantised According to Bohr's theory , electron revolve around the nucels in CIRCULAR orbits Solution :The energy of the electron remains constant only when it is revolving around nucleus' in a particular orbit. During an electronic transition, it gains or loses energy

Discussion

1461.	When conc. acid is added to water, whether the process is exothermic or endothermic ?
Answer» SOLUTION :EXOTHERMIC (HEAT is EVOLVED).

Discussion

1462.	Two electronegativeatoms combine to form
Answer» ionic BOND covalent bond COORDINATE bond can't be predicted Solution :TWO ELECTRONEGATIVE atoms combine to FORM covalent bend,

Discussion

1463.	Which of the following metal does not evolve hydrogen gas on reaction with dilute HCl?
Answer» magnesium iron COPPER aluminium Solution :Copper is below hydrogen in the ACTIVITY SERIES and hence does not evolve hydrogen GAS.

Discussion

1464.	What is meant by homologous series of carbon compounds? Classify the following carbon compounds into two homologous series and name them. C_(3)H_(4), C_(3)H_(6), C_(4)H_(8), C_(5)H_(8), C_(5)H_(10)
Answer» Solution :A group of organic compounds having the same functional group and similar structures in which the SUCCESSIVE members differ by `CH_(2)` group is CALLED HOMOLOGOUS series. Alkynes: `C_(3)H_(4), C_(4)H_(6), C_(5)H_(8)` Alkenes: `C_(3)H_(6), C_(4)H_(8), C_(5)H_(10)`

Discussion

1465.	Write the balanced chemical equation for each of the following. Iron nails become brownish in colour and the blue colour of copper sulphate is converted into light green.
Answer» Solution :`CuSO_(4)(AQ.)+FE(s)toFeSO_(4)(aq.)+Cu(s)`.

Discussion

1466.	Write the characteristics of organic compounds.
Answer» Solution :Organic COMPOUNDS have a high molecular weight and a complex structure. They are mostly insoluble in water, but soluble in organic solvents such as ether, carbon tetrachloride, toluene, ETC. They are highly inflammable in nature. Organic compounds are less reactive compared to inorganic compounds. Hence, the REACTIONS involving organic compounds proceed at slower rates. Mostly organic compounds form covalent bonds in nature. They have lower melting point and boilling point when compared to inorganic compounds They exhibit the phenomenon of isomerism, in which a single molecular formula represents several organic compounds that DIFFER in their physical and chemical properties They are volatile in nature. Organic compounds can be PREPARED in the laboratory.

Discussion

1467.	Write the products obtained when sodium oxide reacts with hydrochloric acid.
Answer» Solution :As a STRONG base, sodium oxide REACTS with hydrochloric acid to give sodium CHLORIDE solution and water. METAL oxide + Acid `to ` SALT + Water `Na_2O + 2HCl+ 2NaCl + H_2O`

Discussion

1468.	Write the balanced chemical equation for thereactions : Aluminium + Copper chloride to Aluminium chloride + Copper
Answer» SOLUTION :`underset("ALUMINIUM")(2Al(s))+ underset("Copper chloride")(3CuCl_(2)(aq)) to underset("Aluminium chloride")(2AlCl_(3)(aq))+ underset("Copper")(3Cu(s))`

Discussion

1469.	You are given a hammer, battery, a bulb, wires and a switch. (a) How coulf you see use them to distinguish between samples of metals and non-metals ? (b) Assess the usefulness of these tests in distinguishing between metals and non-metals.
Answer» Solution :(a) If on hammering, the substance gets break into pieces then it is a non-metal. But if the substance expands, then it is a metal. Test by passing ELECTRIC CURRENT : Prepared the circuit and place the SAMPLE between the clips A and B and switch on the bulb. If the bulb glows than it is metal and vice-versa. (b) Due tomalleability, the metals can be HAMMERED into sheet which can be used for various purposes. Since metals are GOOD conductor of electricity, these are used in designing of wire.

Discussion

1470.	Whatis the pHof 1.0xx10^(-5)molarsolutionof KOH ?
Answer» Solution :`KOH_((AQ)) impliesK_((aq))^(+) +OH_((aq))^(-)`Onemoleof KOHwouldgiveone moleof `OH^(-)`ions . `[OH^(-)]=1xx10^(-5) mol "LITRE"^(-1)` `POH=- log_(10)[OH ^-]=-LOG _(10) [10^5]` `=-(5xx log _(10) ^(10))=-(-5)=5 ` `PH +POH= 14 ` `pH= 14 -pOH =14-5=9`

Discussion

1471.	What effect does the concentration of H^+(aq) ions have on the nature of the solution ?
Answer» Solution :Higher the CONCENTRATION of `H^+` (aq) IONS, greater is the ACIDIC NATURE of the solution.

Discussion

1472.	Which of the following reactions is an esterification one ?
Answer» ` 2CH_(3)OH +2Na to 2CH_(3) Ona+H_(2)` `CH_(3)COOH+NaOH to CH_(3)COONa+H_(2)O` `CH_(3)COOH+ C_(2)H_(5)OH to CH_(3)COOC_(2)H_(5) +H_(2)O` `C_(2)H_(5)OH to C_(2)H_(4)+H_(2)O)` ANSWER :C

Discussion

1473.	What happens to the colour of litmus paper when a drop of acid falls on it?
Answer» COLOUR fades from BLUE it TURNS red from red it turns blue REMAINS unchanged SOLUTION :from blue it turns red

Discussion

1474.	Write the name and formula of the 2^(nd) member of homologous series having general formula C_(n)H_(2n).
Answer» ANSWER :Name : PROPANE Formula: `C_(3)H_(6)`

Discussion

1475.	Write two chemical tests to distinguish ethyne from ethene
Answer» SOLUTION :(i)Ethyne FORMS a red precipitate with ammoniacal solution of copper (I) chloride, whereas ethene does not RESPOND to this TEST. (ii) Ethyne forms a white precipitate with ammoniacal solution of SILVER nitrate , whereas ethenedoes not respond to this test.

Discussion

1476.	What is correct for redox reaction ? (i) Reducing agent undergoes oxidation. (ii) Reducing agent undergoes reduction. (iii) Reduction reaction always occurs at cathode. (iv) Oxidising agent undergo oxidation.
Answer» Only (i), (II) Only (i), (III) Only (iii) GIVEN all Solution :Only (i), (iii)

Discussion

1477.	What are amphoteric substances? Illustrates with an example.
Answer» Solution :A SUBSTANCE is said to be amphoteric if it can BEHAVE either as an ACID or as a base. WATER is the most common amphoteric substance.

Discussion

1478.	Three different elctrolytic cells A, B and C are connectedin separate circuits .Electrolytic cell A contains sodium chloride solution. When the circuit is complete . A bulb in the circuit glows brightly .electrolytic cell B contains acetic acid solution and in this casethe bulbin the circuit glows dimly . The elctrolytic cell C contains sugar solution and the bulb does not glow . Give a reasonfor each of these observations .
Answer» Solution :(i) NaClis a STRONG electrolyte and is completely isonied in solution .THUS the number of ions is large . ` Na Cl(AQ) to Na^(+) +Cl^(-)(aq)` (ii) Acetic ACID being weak electrolyte is PARTIALLY ionised .Thus the number of ions is small . (iii) Sugar is nonelectrolyte ,and it does not produce ions .

Discussion

1479.	The relation between a and r in face- centred cubic lattice
Answer» `R = SQRT a` `r = sqrt 2A` `r = a / (2sqrt2)` All of the above Answer :C

Discussion

1480.	When water freezes into ice
Answer» TEMPERATURE INCREASES. temperature decreases heat is absorbed heat is RELEASED ANSWER :D

Discussion

1481.	What is observed when carbondioxide gas is passed through lime water For a long duration ? Write the chemical equation.
Answer» Solution :LONG duration : A CLEAR solution is obtained DUE to the formation of calcium bicarbonate which is soluble in water `CaCO_(3)(s)+H_(2)O(l)+CO_(2)(g) to Ca(HCO_(3))_(2)(aq)`.

Discussion

1482.	What are the names of compounds? H-overset(H)overset(\|)C=O
Answer» SOLUTION :METHANAL or FORMALDEHYDE.

Discussion

1483.	What are hydrocarbons?
Answer» Solution :The COMPOUNDS COMPOSED of only CARBON and hydrogen atoms are called HYDROCARBONS.

Discussion

1484.	What is the oxidation state of Oxygen in H_(2)O_(2).
Answer» ANSWER :1

Discussion

1485.	What are atuosomes and sex chromosome ?
Answer» Solution :HUMAN CELL contain 23 pairs of chromosomes out of 23 pairs, 22 pairs are called autosomes, REST of 1 pairs, which determine the sex of CHILD is called sex chromosomes.

Discussion

1486.	Write the molecular formula of alcohol which can be derived from butane.
Answer» SOLUTION :BUTANOL - Its MOLECULAR FORMULA is `CH_3-CH_2-CH_2-CH_2-OH` .

Discussion

1487.	What happens when NaCl solution reacts with AgNO_(3) solution. Name the two types of reaction to which it belongs.
Answer» Solution :White PRECIPITATE of silver chloride `(AgCl)` is formed `AgNO_(3)(AQ)+NaCl(aq)toAgCl(s)darr+NaNO_(3)(aq)` The two names of this reaction is (i) DOUBLE displacement reaction (II) Precipitation reaction

Discussion

1488.	Write the balanced chemical equation for each of the following. Barium chloride solution is mixed with copper sulphate solution and a white precipitate is observed.
Answer» Solution :`BaCl_(2)(aq.)+CuSO_(4)(aq.)toCuCl_(2)(aq.)+BaSO_(4)(s)DARR`.

Discussion

1489.	What is lime water test for the detection of carbon dioxide?
Answer» Solution :When carbon dioxide gas is passed through LIME water it turns milky due to the fonnation of a milky suspension (PRECIPITATE) of calcium carbonate. Carbon dioxide is produced by the action of DILUTE HCI on sodium carbonate. `Na_2CO_3(s)+2HCl(aq)to2NaCl+H_2O(l)+CO_2` Carbon dioxide gas which prod.uccd in this reaction is passed through lime water that CHANGES to a milky colour due to the FORMATION of calcium carbonate. `Ca(OH)_2(aq)+CO_2(g)toCaCO_3+H_2O(aq)`

Discussion

1490.	Wrtie the flow chart of long form of periodic table.
Answer» SOLUTION :

Discussion

1491.	What are the constituents of solder alloy ? Which property of solder makes it suitable for welding electrical wires ?
Answer» COPPER, zinc copper, tin lead, zinc lead, tin Answer :D

Discussion

1492.	Which one of the following has the largest atomic radius?a) lithium b) sodiumc) potassium d) chlorine
Answer» a)Lithium b)SODIUM C)POTASSIUM d)Chlorine Solution :Potassium

Discussion

1493.	Which of the following method is not used in preparing a base?
Answer» BURNING of METAL in air adding water to a metal oxide REACTION between an acid and base heating metal carbonates SOLUTION :reaction between an acid and base

Discussion

1494.	What happens when (write balanced chemical equations only) A mixture of iron filings and dilute sulphuric acid is heated.
Answer» SOLUTION :`Fe+H_(2)SO_(4)toFeSO_(4)+H_(2)`

Discussion

1495.	Two acids 'A' and 'B' were kept in breakers .Acid 'A' undergoes partial dissociation in water,whereas acid 'B' undergoes complete dissociation in water. (i)Of the two acids 'A' and 'B', which is weak acid and which is strong acid? (ii)What is a weak acid? (iii)What is a strong acid? (iv)Give one example each.
Answer» Solution :(i)Of the two acids .A. and .B. ,.A. isa WEAK acid and .B. is a strong acid. (ii)Weak acid the one which IONISES partially when dissolved in water. (iii)A strong acid is the one which ionises completely when dissolved in water. (iv)Weak acid -Acetic acid`(CH_(3)COOH)` Strong acid-Sulphuric acid `(H_(2)SO_(4))`

Discussion

1496.	Which one of the following has the largest atomic radius?
Answer» Li F K Br Solution :K

Discussion

1497.	Write the valency of an element having atomic number 13.
Answer» ANSWER :3

Discussion

1498.	Which of the statements about the reaction below are incorrect ? 2PbO(s)+ C(s) to 2Pb(s)+ CO_(2)(g) (a) Lead is getting reduced. (b) Carbon dioxide is getting oxidised. (c) Carbon is getting oxidised. (d) Lead oxide is getting reduced.
Answer» (a) and (B) (a) and (C) (a), (b) and (c) all Solution :(a) and (b)

Discussion

1499.	w' amount of work is done by the system and 'q' amount of heat is supplied to the system. What type of system would it be?
Answer» SOLUTION :CLOSED SYSTEM

Discussion

1500.	Use Mendeleev's periodic table to predict the formulae for the oxides of the following elements : K, C, A, Si, Ba
Answer» SOLUTION :

Discussion

Explore topic-wise InterviewSolutions in .

Write the name and molecular formula of an alkyne having four carbon atoms.

What type of oxides are formed, when non metals combine with oxygen?

When an atom occupies an interstitial site it is known as

Write one example of each of the following:(a) A metal and a non-metal which are liquids at room temperature. (b) A metal which is very soft and a non-metal which is very hard. (c) A metal which has very low melting point and a non-metal which has very high melting point.

What are noble metals?

Which of the following elements react(s) whit acids to form salts (a salt) ?

What is called rancidity ?

Valency of an element is determined by the number of electrons present in the first shell.

Which one of the following will be displaced from its salt solution by copper?

Which of the following statements is false

When conc. acid is added to water, whether the process is exothermic or endothermic ?

Two electronegativeatoms combine to form

Which of the following metal does not evolve hydrogen gas on reaction with dilute HCl?

What is meant by homologous series of carbon compounds? Classify the following carbon compounds into two homologous series and name them. C_(3)H_(4), C_(3)H_(6), C_(4)H_(8), C_(5)H_(8), C_(5)H_(10)

Write the balanced chemical equation for each of the following. Iron nails become brownish in colour and the blue colour of copper sulphate is converted into light green.

Write the characteristics of organic compounds.

Write the products obtained when sodium oxide reacts with hydrochloric acid.

Write the balanced chemical equation for thereactions : Aluminium + Copper chloride to Aluminium chloride + Copper

You are given a hammer, battery, a bulb, wires and a switch. (a) How coulf you see use them to distinguish between samples of metals and non-metals ? (b) Assess the usefulness of these tests in distinguishing between metals and non-metals.

Whatis the pHof 1.0xx10^(-5)molarsolutionof KOH ?

What effect does the concentration of H^+(aq) ions have on the nature of the solution ?

Which of the following reactions is an esterification one ?

What happens to the colour of litmus paper when a drop of acid falls on it?

Write the name and formula of the 2^(nd) member of homologous series having general formula C_(n)H_(2n).

Write two chemical tests to distinguish ethyne from ethene

What is correct for redox reaction ? (i) Reducing agent undergoes oxidation. (ii) Reducing agent undergoes reduction. (iii) Reduction reaction always occurs at cathode. (iv) Oxidising agent undergo oxidation.

What are amphoteric substances? Illustrates with an example.

The relation between a and r in face- centred cubic lattice

When water freezes into ice

What is observed when carbondioxide gas is passed through lime water For a long duration ? Write the chemical equation.

What are the names of compounds? H-overset(H)overset(|)C=O

What are hydrocarbons?

What is the oxidation state of Oxygen in H_(2)O_(2).

What are atuosomes and sex chromosome ?

Write the molecular formula of alcohol which can be derived from butane.

What happens when NaCl solution reacts with AgNO_(3) solution. Name the two types of reaction to which it belongs.

Write the balanced chemical equation for each of the following. Barium chloride solution is mixed with copper sulphate solution and a white precipitate is observed.

What is lime water test for the detection of carbon dioxide?

Wrtie the flow chart of long form of periodic table.

What are the constituents of solder alloy ? Which property of solder makes it suitable for welding electrical wires ?

Which one of the following has the largest atomic radius?a) lithium b) sodiumc) potassium d) chlorine

Which of the following method is not used in preparing a base?

What happens when (write balanced chemical equations only) A mixture of iron filings and dilute sulphuric acid is heated.

Which one of the following has the largest atomic radius?

Write the valency of an element having atomic number 13.

Which of the statements about the reaction below are incorrect ? 2PbO(s)+ C(s) to 2Pb(s)+ CO_(2)(g) (a) Lead is getting reduced. (b) Carbon dioxide is getting oxidised. (c) Carbon is getting oxidised. (d) Lead oxide is getting reduced.

w' amount of work is done by the system and 'q' amount of heat is supplied to the system. What type of system would it be?

Use Mendeleev's periodic table to predict the formulae for the oxides of the following elements : K, C, A, Si, Ba