You are given samples of three metals. Sodium, magnesium and copper. Suggest any two activities to arrange them in order of decreasing activity. -Chemistry

You are given samples of three metals. Sodium, magnesium and copper. Suggest any two activities to arrange them in order of decreasing activity. -Chemistry
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Answer :

Activity 1: Sodium reacts with cold water vigorously to form sodium hydroxide and hydrogen gas Magnesium does not react with cold water but with hot water to form magnesium ! hydroxide and hydrogen gas. Hence sodium is more reactive than magnesium.
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Which of the following is the correct arrangement of the given metals in ascending order of their reactivity? Zinc, Iron, Magnesium, Sodium A) Zinc > Iron > Magnesium > Sodium B) Sodium > Magnesium > Iron > Zinc C) Sodium > Zinc > Magnesium > Iron D) sodium > Magnesium > Zinc > Iron

Description : Which of the following is the correct arrangement of the given metals in ascending order of their reactivity? Zinc, Iron, Magnesium, Sodium A) Zinc > Iron > Magnesium > Sodium B) Sodium > Magnesium > Iron > Zinc C) Sodium > Zinc > Magnesium > Iron D) sodium > Magnesium > Zinc > Iron

Last Answer : D) sodium > Magnesium > Zinc > Iron

Consider the following places: 2. Shimla 3. Gangtok 4. Mumbai 5. Delhi Arrange these places in decreasing order of their atmospheric pressure on their ground surface using the codes given below: [CDS 2002] (a) 3, 4, 1, 2 (b) 4, 3, 2, 1 (c) 3, 1, 4, 2 (d) 2, 4, 1, 3

Description : Consider the following places: 2. Shimla 3. Gangtok 4. Mumbai 5. Delhi Arrange these places in decreasing order of their atmospheric pressure on their ground surface using the codes given below: [CDS 2002] (a) 3, 4, 1, 2 (b) 4, 3, 2, 1 (c) 3, 1, 4, 2 (d) 2, 4, 1, 3

Last Answer : Ans: (b)

Arrange the following in order of decreasing reactivity towards alkanes. HCl, HBr, HI, HF

Description : Arrange the following in order of decreasing reactivity towards alkanes. HCl, HBr, HI, HF

Last Answer : Ans. HI> HBr> HCl >HF

Arrange the following in the decreasing order of Vander Waal’s radii: Cl, H, O, N.

Description : Arrange the following in the decreasing order of Vander Waal’s radii: Cl, H, O, N.

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Arrange the first group elements in the decreasing order of Hydration Enthalpy

Description : Arrange the first group elements in the decreasing order of Hydration Enthalpy 

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Arrange the following size reduction equipment in the decreasing order of the average particle size produced by each of them. (A) Jaw crusher, Ball mill, Fluid energy mill(B) Ball mill, Jaw crusher, Fluid energy mill(C) Fluid energy mill, Jaw crusher, Ball mill(D) Fluid energy mill, Ball mill, Jaw crusher

Description : Arrange the following size reduction equipment in the decreasing order of the average particle size produced by each of them. (A) Jaw crusher, Ball mill, Fluid energy mill (B) Ball mill, Jaw crusher, Fluid ... C) Fluid energy mill, Jaw crusher, Ball mill (D) Fluid energy mill, Ball mill, Jaw crusher

Last Answer : (A) Jaw crusher, Ball mill, Fluid energy mill

Write chemical equation reactions taking place when carried out with the help of (a) Iron reacts with steam (b) Magnesium reacts with dil HCl (c) Copper is heated in air. -Chemistry

Description : Write chemical equation reactions taking place when carried out with the help of (a) Iron reacts with steam (b) Magnesium reacts with dil HCl (c) Copper is heated in air. -Chemistry

Last Answer : This is the Answer.

You are provided with magnesium ribbon and sulpher powder. Explain with the help of an activity that metal oxides are basic and non-metal oxide are acidic in nature. -Chemistry

Description : You are provided with magnesium ribbon and sulpher powder. Explain with the help of an activity that metal oxides are basic and non-metal oxide are acidic in nature. -Chemistry

Last Answer : Aim: To test the nature of oxides formed by metals and non-metals. Materials Required: Sulphur powder, Mg ribbon, water, blue litmus paper, red litmus paper. Procedure: 1.Take magnesium ribbon ... the metallic oxides are basic in nature whereas most of the non-metallic oxides are acidic in nature.

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Description : Which one of the following metals does not form amalgam? (1) Zinc (2) Copper (3) Magnesium (4) Iron

Last Answer : (4) Iron Explanation: The definition of an amalgam is a mixture of metals and mercury, which can be man-made or can be naturally occurring.

Which one of the following metals is essential to the structure and functioning of hemoglobin? w) copper x) magnesium y) tin z) iron

Description : Which one of the following metals is essential to the structure and functioning of hemoglobin? w) copper x) magnesium y) tin z) iron

Last Answer : ANSWER: Z -- IRON

Which of the following metals is a solid at room temperature, yet melts in your hand? w) gallium x) cesium y) sodium z) magnesium

Description : Which of the following metals is a solid at room temperature, yet melts in your hand? w) gallium x) cesium y) sodium z) magnesium

Last Answer : ANSWER: W -- GALLIUM

Which of the following metals melts in your hand? w) gallium x) cesium y) sodium z) magnesium

Description : Which of the following metals melts in your hand? w) gallium x) cesium y) sodium z) magnesium

Last Answer : ANSWER: W -- GALLIUM

Cinnabar, pyrite and galena are minerals which consist of one or more metals combined with the same element. Which one of the following is the element that is common to all three of these minerals? Is it: w) iron x) copper y) sulfur z) sodium

Description : Cinnabar, pyrite and galena are minerals which consist of one or more metals combined with the same element. Which one of the following is the element that is common to all three of these minerals? Is it: w) iron x) copper y) sulfur z) sodium

Last Answer : ANSWER: C-- SULFUR

Arrange the following in decreasing order of rate of nitration :-

Description : Arrange the following in decreasing order of rate of nitration :-

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Arrange the following in decreasing order of acidic strength:

Description : Arrange the following in decreasing order of acidic strength:

Last Answer : Arrange the following in decreasing order of acidic strength: A. `I gt II gt III gt IV` B. `IV gt III gt II ... III gt I` D. `IV gt II gt III gt I`

Arrange the following compounds in decreasing order of reactivity for EAR :- (I) `CH_(2)=CH_(2)` (II) `CH_(3)-CH=CH_(2)` (III) `Ph_(2)C=CH-CH_(3)` (IV

Description : Arrange the following compounds in decreasing order of reactivity for EAR :- (I) `CH_(2)=CH_(2)` (II) `CH_(3)-CH=CH_(2)` (III) `Ph_(2)C=CH-CH_(3)` (IV

Last Answer : Arrange the following compounds in decreasing order of reactivity for EAR :- (I) `CH_(2)=CH_(2)` (II) `CH_(3)- ... I gt IV` D. `II gt III gt IV gt I`

Arrange the compounds in order of decreasing acidic strength : (I) `ClCH_(2)-CH_(2)-OH` (II) `Cl_(2)CH-CH_(2)-OH` (III) `Cl-CH_(2)-CH_(2)-CH_(2)-OH` (

Description : Arrange the compounds in order of decreasing acidic strength : (I) `ClCH_(2)-CH_(2)-OH` (II) `Cl_(2)CH-CH_(2)-OH` (III) `Cl-CH_(2)-CH_(2)-CH_(2)-OH` (

Last Answer : Arrange the compounds in order of decreasing acidic strength : (I) `ClCH_(2)-CH_(2)-OH` (II) `Cl_(2)CH-CH_(2 ... IV gt III` D. `II gt I gt III gt IV`

Arrange the following acid in decreasing order of their acidic strength : (I) `CH_(3)-OH` (II) `CH_(3)CH_(2)-OH` (III) `CH_(3)-underset(CH_(3))underse

Description : Arrange the following acid in decreasing order of their acidic strength : (I) `CH_(3)-OH` (II) `CH_(3)CH_(2)-OH` (III) `CH_(3)-underset(CH_(3))underse

Last Answer : Arrange the following acid in decreasing order of their acidic strength : (I) `CH_(3)-OH` (II) `CH_(3)CH_(2)- ... II gt IV` D. `II gt IV gt III gt I`

Arrange the following in decreasing order of their stability :- `(I) CH_(3)-overset(oplus)(CH_(2)) " "(II) CH_(3)-underset(CH_(3))underset(|)overset(o

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Arrange the following compounds in decreasing order of nucleophilic addition with semicarbazide `NH_(2)NHCONH_(2)` i.e., `ddot(N)H_(2)-ddot(Z)`

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Arrange the following compounds in decreasing order of nucleophilic addition with semicarbazide `NH_(2)NHCONH_(2)` i.e., `ddot(N)H_(2)-ddot(Z)`

Description : Arrange the following compounds in decreasing order of nucleophilic addition with semicarbazide `NH_(2)NHCONH_(2)` i.e., `ddot(N)H_(2)-ddot(Z)`

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Description : Arrange `CFC, CH_(4), N_(2)O, and CO_(2)` in decreasing order according to their contribution in greenhouse effect:

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Arrange the following free radicals in order of decreasing stability: Methyl(I), Vinly(II), Allyl(III), Benzyl(IV)

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Arrange the carbanions, `(CH_(3))_(3)bar(C),bar(C)Cl_(3),(CH_(3))_(2)bar(C)H,C_(6)H_(5)bar(C)H_(2)`, in order of their decreasing stability

Description : Arrange the carbanions, `(CH_(3))_(3)bar(C),bar(C)Cl_(3),(CH_(3))_(2)bar(C)H,C_(6)H_(5)bar(C)H_(2)`, in order of their decreasing stability

Last Answer : Arrange the carbanions, `(CH_(3))_(3)bar(C),bar(C)Cl_(3),(CH_(3))_(2)bar(C)H,C_(6)H_(5)bar(C)H_(2 ... (2)bar(C)HgtC_(6)H_(5)bar(C)H_(2)gtbar(C)Cl_(3)`

Arrange the following in order of decreasing tendency towards `S_(N^(2))` reaction : `{:(underset("(I)")(CH_(3)CH_(2)CH_(2)CH_(2)Cl)", "underset("(II)

Description : Arrange the following in order of decreasing tendency towards `S_(N^(2))` reaction : `{:(underset("(I)")(CH_(3)CH_(2)CH_(2)CH_(2)Cl)", "underset("(II)

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Arrange the following cities in decreasing order of the rainfall they receive from the south-west monsoons in summer months: 1. Allahabad 2. Kolkata 3. Delhi 4. Patna (a) 2, 4, 1, 3 (b) 3, 1, 4, 2 (c) 1, 4, 3, 2 (d) 2, 4, 3, 1

Description : Arrange the following cities in decreasing order of the rainfall they receive from the south-west monsoons in summer months: 1. Allahabad 2. Kolkata 3. Delhi 4. Patna (a) 2, 4, 1, 3 (b) 3, 1, 4, 2 (c) 1, 4, 3, 2 (d) 2, 4, 3, 1

Last Answer : Ans: (d)

Write the molecular formulae of: 1. Copper oxide 2. Iron (III) chloride 3. Sodium hydroxide 4. Iron (II) sulphide 5. Lead (II) oxide 6. Hydrogen nitrate (nitric acid) 7. Hydrogen sulphate (sulphuric acid) 8. Calcium hydroxide 9. Magnesium carbonate 10.Ammonium carbonate

Description : Write the molecular formulae of: 1. Copper oxide 2. Iron (III) chloride 3. Sodium hydroxide 4. Iron (II) sulphide 5. Lead (II) oxide 6. Hydrogen nitrate (nitric ... Hydrogen sulphate (sulphuric acid) 8. Calcium hydroxide 9. Magnesium carbonate 10.Ammonium carbonate

Last Answer : 1. Copper oxide - CuO 2. Iron (III) chloride - FeCl3 3. Sodium hydroxide - NaOH 4. Iron (II) sulphide - FeS 5. Lead (II) oxide - PbO 6. Hydrogen nitrate (nitric acid) - HNO3 7. ... ) - H2SO4 8. Calcium hydroxide - Ca(OH)2 9. Magnesium carbonate - MgCO3 10.Ammonium carbonate - (NH4)2CO3

Define the term valency. What is the valency for magnesium and copper? -Chemistry 9th

Description : Define the term valency. What is the valency for magnesium and copper? -Chemistry 9th

Last Answer : The no.of electrons required for the element to be octate or duplate is known as valency. Magnesium = 2 Copper = 1 hope this helps u

The metals with very low melting points which melts by the temperature of palm are A) Sodium and potassium B) Lead and magnesium C) Aluminium and zinc D) Gallium and caesium

Description : The metals with very low melting points which melts by the temperature of palm are A) Sodium and potassium B) Lead and magnesium C) Aluminium and zinc D) Gallium and caesium

Last Answer : D) Gallium and caesium

Which of the following metals reacts violently with water? (A) Mercury (B) Sodium (C) Calcium (D) Magnesium

Description : Which of the following metals reacts violently with water? (A) Mercury (B) Sodium (C) Calcium (D) Magnesium

Last Answer : Option B

Metals are generally hard, which of the following metal is an exception and can be cut with a knife? a) iron b)sodium c)gold d)magnesium

Description : Metals are generally hard, which of the following metal is an exception and can be cut with a knife? a) iron b)sodium c)gold d)magnesium

Last Answer : b)sodium

Which one of the following metals occurs in nature in free state? (1) Gold (2) Sodium (3) Aluminium (4) Copper

Description : Which one of the following metals occurs in nature in free state? (1) Gold (2) Sodium (3) Aluminium (4) Copper

Last Answer : (1) Gold Explanation: Gold is found on every continent on Earth, except Antarctica. The largest amounts of gold on Earth are found in the oceans - but it is not yet feasible to extract gold from seawater.

Which of the following metals is stored in kerosene oil? (1) Platinum (2) Copper (3) Sodium (4) Gold

Description : Which of the following metals is stored in kerosene oil? (1) Platinum (2) Copper (3) Sodium (4) Gold

Last Answer : (3) Sodium Explanation: Owing to its extreme reactivity, sodium occurs in nature only combined in compounds never as a pure elemental metal.

Which of the following metals is NOT obtained by reduction using carbon? (1) Copper (2) Sodium (3) Iron (4) Zinc

Description : Which of the following metals is NOT obtained by reduction using carbon? (1) Copper (2) Sodium (3) Iron (4) Zinc

Last Answer : (2) Sodium Explanation: Metals such as zinc, iron and copper are present in ores as their oxides. Each of these oxides is heated with carbon to obtain the metal.

The metals commonly used for electroplating are – (1) Gold, Sodium and Chromium (2) Chromium, Copper and Nickel (3) Nickel, Lead and Chromium (4) Gold, Sodium and Potassium

Description : The metals commonly used for electroplating are – (1) Gold, Sodium and Chromium (2) Chromium, Copper and Nickel (3) Nickel, Lead and Chromium (4) Gold, Sodium and Potassium

Last Answer : (2) Chromium, Copper and Nickel Explanation: The process of electroplating takes place as metals in ionic form move from a positive to negative electrode. An electric current passing through the ... ability of metal objects. Plating protects by one of two ways, either sacrificially or mechanically.

Which of the following metals can be obtained from its ore only by electrolysis of a molten salt ? w) cobalt x) chromium y) copper z) sodium

Description : Which of the following metals can be obtained from its ore only by electrolysis of a molten salt ? w) cobalt x) chromium y) copper z) sodium

Last Answer : ANSWER: Z -- SODIUM

The metals commonly used for electroplating are (1) Gold, Sodium and Chromium (2) Chromium, Copper and Nickel (3) Nickel, Lead and Chromium (4) Gold, Sodium and Potassium

Description : The metals commonly used for electroplating are (1) Gold, Sodium and Chromium (2) Chromium, Copper and Nickel (3) Nickel, Lead and Chromium (4) Gold, Sodium and Potassium

Last Answer : Chromium, Copper and Nickel

Arrange the following activities of interaction in logical order (i) Analysis of the work done (ii) Planning and preparation (iii) Presentation of material (iv) Modification and improvement (a) (0 (ii), (Hi), (iv) (b) (ii), (Hi), (i), (iv) (c) (iv). (/), (ii), (Hi) (d) (i), (Hi), (iv). (ii)

Description : Arrange the following activities of interaction in logical order (i) Analysis of the work done (ii) Planning and preparation (iii) Presentation of material (iv) Modification and improvement (a) (0 (ii), (Hi), (iv) (b) (ii), (Hi), (i), (iv) (c) (iv). (/), (ii), (Hi) (d) (i), (Hi), (iv). (ii)

Last Answer : (b) (ii), (Hi), (i), (iv)

The reactivity series is a list of metals arranged in order of A) Increasing reactivity B) Decreasing reactivity C) Increasing and decreasing reactivity D) None of the above

Description : The reactivity series is a list of metals arranged in order of A) Increasing reactivity B) Decreasing reactivity C) Increasing and decreasing reactivity D) None of the above

Last Answer : B) Decreasing reactivity

Absorption of calcium decreases if there is high concentration in the diet of (A) Copper (B) Sodium (C) Magnesium (D) Cadmium

Description : Absorption of calcium decreases if there is high concentration in the diet of (A) Copper (B) Sodium (C) Magnesium (D) Cadmium

Last Answer : Answer : C

Alcohol dehydrogenase from liver contains (A) Sodium (B) Copper (C) Zinc (D) Magnesium

Description : Alcohol dehydrogenase from liver contains (A) Sodium (B) Copper (C) Zinc (D) Magnesium

Last Answer : Answer : C

The displacement reaction between iron (III) oxide and a metal X is used for welding the rail tracks. Here X is: (a) Copper granules (b) Magnesium ribbon (c) Sodium pellets (d) Aluminum dust

Description : The displacement reaction between iron (III) oxide and a metal X is used for welding the rail tracks. Here X is: (a) Copper granules (b) Magnesium ribbon (c) Sodium pellets (d) Aluminum dust

Last Answer : (d) Aluminum dust

Which one is the major component of Bordeaux mixture a) Copper sulphate b) Sodium chloride c) Calcium chloride d) Magnesium sulphate

Description : Which one is the major component of Bordeaux mixture a) Copper sulphate b) Sodium chloride c) Calcium chloride d) Magnesium sulphate

Last Answer : a) Copper sulphate

Name the ion responsible for unmasking of active sites for myosin for cross-bridge activity during muscle contraction. (a) Calcium (b) Magnesium (c) Sodium (d) Potassium

Description : Name the ion responsible for unmasking of active sites for myosin for cross-bridge activity during muscle contraction. (a) Calcium (b) Magnesium (c) Sodium (d) Potassium

Last Answer : (a) Calcium

Arrange the following compounds in decreasing orders of rate of hydration. `(X) C Cl_(3)CHO " " (Y) CH_(3)CHO " " (Z)CH_(3)COCH_(3) " " (W) CF_(3)CHO`

Description : Arrange the following compounds in decreasing orders of rate of hydration. `(X) C Cl_(3)CHO " " (Y) CH_(3)CHO " " (Z)CH_(3)COCH_(3) " " (W) CF_(3)CHO`

Last Answer : Arrange the following compounds in decreasing orders of rate of hydration. `(X) C Cl_(3)CHO ... . WgtZgtXgtY B. WgtXgtYgtZ C. WgtYgtZgtX D. WgtZgtYgtX

Arrange the following compounds in decreasing orders of rate of hydration. `(X) C Cl_(3)CHO " " (Y) CH_(3)CHO " " (Z)CH_(3)COCH_(3) " " (W) CF_(3)CHO`

Description : Arrange the following compounds in decreasing orders of rate of hydration. `(X) C Cl_(3)CHO " " (Y) CH_(3)CHO " " (Z)CH_(3)COCH_(3) " " (W) CF_(3)CHO`

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Arrange the following carbanions in decreasing orde of stability: `HC-=bar(C)(I)," "H_(3)C-C-=bar(C)(II),` `H_(2)C=bar(C)H(III)," "H_(3)C-bar(C)H_(2)(

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Last Answer : Arrange the following carbanions in decreasing orde of stability: `HC-=bar(C)(I)," "H_(3 ... `IIgtIgtIIIgtIV` C. `IVgtIIIgtIIgtI` D. `IgtIIgtIIIgtIV`

Which of the following is arranged in order of decreasing conductivity? (1) Copper, Aluminium, Steel, Silver (2) Aluminium, Silver, Copper, Steel (3) Copper, Silver, Aluminium, Steel (4) Silver, Copper, Aluminium, Steel

Description : Which of the following is arranged in order of decreasing conductivity? (1) Copper, Aluminium, Steel, Silver (2) Aluminium, Silver, Copper, Steel (3) Copper, Silver, Aluminium, Steel (4) Silver, Copper, Aluminium, Steel

Last Answer : (4) Silver, Copper, Aluminium, Steel Explanation: Copper ; 9% less conductive than silver; aluminium is 10% less conductive than copper; while steel is the least conductive among the given options. The most electrically conductive metal is silver.

Which of the following is arranged in order of decreasing conductivity? (1) Copper, Aluminium, Steel, Silver (2) Aluminium, Silver, Copper, Steel (3) Copper, Silver, Aluminium, Steel (4) Silver, Copper, Aluminium, Steel

Description : Which of the following is arranged in order of decreasing conductivity? (1) Copper, Aluminium, Steel, Silver (2) Aluminium, Silver, Copper, Steel (3) Copper, Silver, Aluminium, Steel (4) Silver, Copper, Aluminium, Steel 

Last Answer : Silver, Copper, Aluminium, Steel

.Identify the physical and chemical changes from the following (i)Burning of magnesium in air (ii)Electrolysis of water (iii)Tarnishing of silver spoon (iv)Sublimation of iodine -Chemistry

Description : .Identify the physical and chemical changes from the following (i)Burning of magnesium in air (ii)Electrolysis of water (iii)Tarnishing of silver spoon (iv)Sublimation of iodine -Chemistry

Last Answer : (i) Burning of magnesium in air : Chemical change (ii) Tarnishing of silver spoon : Chemical change (iii) Sublimation of iodine : Physical change (iv) Electrolysis of water to form hydrogen and oxygen is also a chemical change.