(i) Substances oxidised is Na as it gains oxygen and oxygen is reduced. (ii) Substances reduced is Cu as hydrogen is oxidised as it gains oxygen. -Chemistry-10

(i) Substances oxidised is Na as it gains oxygen and oxygen is reduced. (ii) Substances reduced is Cu as hydrogen is oxidised as it gains oxygen. -Chemistry-10
by

1 Answer

Answer :

During this reaction, the sodium is gaining oxygen and is being oxidized. Oxygen is getting reduced. During this reaction, copper oxide is losing oxygen and is being reduced. The hydrogen is gaining oxygen and is being oxidized.
by

Related questions

Identify the substances that are oxidised and the substances which are reduced in the following reactions. (i) 4Na(s) + O2(g) → 2Na2O(s) (ii) CuO (s) + H2(g) → Cu (s) + H2O(l) -Chemistry-10

Description : Identify the substances that are oxidised and the substances which are reduced in the following reactions. (i) 4Na(s) + O2(g) → 2Na2O(s) (ii) CuO (s) + H2(g) → Cu (s) + H2O(l) -Chemistry-10

Last Answer : (i) Substances oxidised is Na as it gains oxygen and oxygen is reduced. (ii) Substances reduced is Cu as hydrogen is oxidised as it gains oxygen.

Write the balanced equation for the following chemical reactions. (i) Hydrogen + Chlorine → Hydrogen chloride (ii) Barium chloride + Aluminium sulphate → Barium sulphate + Aluminium chloride (iii) Sodium + Water → Sodium hydroxide + Hydrogen -Chemistry-10

Description : Write the balanced equation for the following chemical reactions. (i) Hydrogen + Chlorine → Hydrogen chloride (ii) Barium chloride + Aluminium sulphate → Barium sulphate + Aluminium chloride (iii) Sodium + Water → Sodium hydroxide + Hydrogen -Chemistry-10

Last Answer : (i) H2 + Cl2 → 2HCl (ii) 3 BaCl2 + Al2(SO4)3 → BaSO4 + 2 AlCl3 (iii) 2Na + 2H2O → 2NaOH + H2↑

A solution of a substance ‘X’ is used for white washing. (i) Name the substance ‘X’ and write its formula. (ii) Write the reaction of the substance ‘X’ named in (i) above with water. -Chemistry-10

Description : A solution of a substance ‘X’ is used for white washing. (i) Name the substance ‘X’ and write its formula. (ii) Write the reaction of the substance ‘X’ named in (i) above with water. -Chemistry-10

Last Answer : (i) The substance whose solution in water is used for white washing is calcium oxide (or quick lime). Its formula is CaO.

What are metalloids? Explain by giving examples. -Chemistry-10

Description : What are metalloids? Explain by giving examples. -Chemistry-10

Last Answer : Metalloids are elements which show some properties of metals and some properties of non-metals. Examples: Silicon, boron, arsenic, antimony, germanium, tellurium, polonium.

What happens when baking soda is heated? -Chemistry-10

Description : What happens when baking soda is heated? -Chemistry-10

Last Answer : Sodium hydrogen carbonate (also known as sodium bicarbonate or bicarbonate of soda) has the chemical formula NaHCO3. When it is heated above about 80°C it begins to break down, forming sodium carbonate, water and carbon dioxide. This type of reaction is called a thermal decomposition.

Why is plaster of paris stored in a moisture proof container? -Chemistry-10

Description : Why is plaster of paris stored in a moisture proof container? -Chemistry-10

Last Answer : Plaster of Paris in contact with moisture (water) changes to solid hard mass, gypsum. Therefore, it gets wasted. Hence it should be stored in moisture proof containers.

Give an example of a double displacement reaction other than the one given in Activity 1.10 -Chemistry-10

Description : Give an example of a double displacement reaction other than the one given in Activity 1.10 -Chemistry-10

Last Answer : Sodium hydroxide and hydrochloric acid react to form sodium chloride and water.

An iron nail is dipped in the solution of copper sulphate for about 30 minutes. State the change in colour observed. Give reason for the change. -Chemistry-10

Description : An iron nail is dipped in the solution of copper sulphate for about 30 minutes. State the change in colour observed. Give reason for the change. -Chemistry-10

Last Answer : When an iron nail is dipped in copper sulphate solution, the displacement reaction takes place. The colour of copper sulphate solution fades due to the formation of light green solution of iron sulphate.

Why does the colour of copper sulphate solution change when an iron nail is dipped in it ? -Chemistry-10

Description : Why does the colour of copper sulphate solution change when an iron nail is dipped in it ? -Chemistry-10

Last Answer : When an iron nail is dipped in copper sulphate solution, the displacement reaction takes place. The colour of copper sulphate solution fades due to the formation of light green solution of iron sulphate.

Why is the amount of gas collected in one of the test tubes in text book Activity 1.7 (i.e., electrolysis of water) double of the amount collected in the other? Name this gas. -Chemistry-10

Description : Why is the amount of gas collected in one of the test tubes in text book Activity 1.7 (i.e., electrolysis of water) double of the amount collected in the other? Name this gas. -Chemistry-10

Last Answer : In Activity 1.7, water is electrolysed to give H2 gas at one electrode and O2 gas at the other electrode. 2H2O(l) → 2H2(g) + O2(g) Thus two molecules of water on electrolysis give two ... oxygen gas or in other words the amount of hydrogen gas collected would be double than that of oxygen gas.

Write a balanced chemical equation with state symbols for the following reactions : -Chemistry-10

Description : Write a balanced chemical equation with state symbols for the following reactions : -Chemistry-10

Last Answer : (i) BaCl2 (aq) + Na2SO4 (aq) → BaSO4(s) + 2NaCl (aq) (ii) NaOH (aq) + HCl(aq) → NaCl(aq) + H2O(l)

Why should a magnesium ribbon be cleaned before burning in air ? -Chemistry-10

Description : Why should a magnesium ribbon be cleaned before burning in air ? -Chemistry-10

Last Answer : Magnesium gets covered with a layer of magnesium oxide when kept in air for a long time. This layer hinders the burning of magnesium. Hence, it is to be cleaned before burning.

15. An object 2 cm high is placed at a distance of 64 cm from a white screen. On placing a convex lens at a distance of 32 cm from the object it is found that a distinct image of the object is formed on the screen. What is the focal length of the conve -Chemistry-10

Description : 15. An object 2 cm high is placed at a distance of 64 cm from a white screen. On placing a convex lens at a distance of 32 cm from the object it is found that a distinct image of the object is formed on the screen. What is the focal length of the conve -Chemistry-10

Last Answer : Since, object-screen distance is double of object-lens separation, the object is at a distance of 2f from the lens and the image should be of the same size of the object.

14. An object 2 cm in size is placed 30 cm in front of a concave mirror of focal length 15 cm. At what distance from the mirror should a screen be placed in order to obtain a sharp image? What will be the nature and the size of the -Chemistry-10

Description : 14. An object 2 cm in size is placed 30 cm in front of a concave mirror of focal length 15 cm. At what distance from the mirror should a screen be placed in order to obtain a sharp image? What will be the nature and the size of the -Chemistry-10

Last Answer : Answer. hope this helps you

13. A ray of light, incident obliquely on a face of a rectangular glass slab placed in air, emerges from the opposite face parallel to the incident ray. State two factors on which the lateral displacement of the emergent ray depends. [Foreign] -Chemistry-10

Description : 13. A ray of light, incident obliquely on a face of a rectangular glass slab placed in air, emerges from the opposite face parallel to the incident ray. State two factors on which the lateral displacement of the emergent ray depends. [Foreign] -Chemistry-10

Last Answer : Lateral displacement depends on the: angle of incidence, thickness of slab, and refractive index of the material. (any two)

12. Draw ray diagrams to represent the nature, position and relative size of the image formed by a convex lens for the object placed: -Chemistry-10

Description : 12. Draw ray diagrams to represent the nature, position and relative size of the image formed by a convex lens for the object placed: -Chemistry-10

Last Answer : Answer. hope this helps you

10. Which kind of mirrors are used in the headlights of a motor-car and why? [Foreign] -Chemistry-10

Description : 10. Which kind of mirrors are used in the headlights of a motor-car and why? [Foreign] -Chemistry-10

Last Answer : Answer. Concave mirror, to get the parallel beam of light.

11. Explain with the help of a diagram, why a pencil partly immersed in water appears to be bent at the water surface. [Delhi] -Chemistry-10

Description : 11. Explain with the help of a diagram, why a pencil partly immersed in water appears to be bent at the water surface. [Delhi] -Chemistry-10

Last Answer : Answer. Light from different points on the pencil, immersed in water refracts and appears to come from a point above the original position.

7. Redraw the given diagram and show the path of the refracted ray: [All India(C)] -Chemistry-10

Description : 7. Redraw the given diagram and show the path of the refracted ray: [All India(C)] -Chemistry-10

Last Answer : Answer. hope this helps you

6. “The refractive index of diamond is 2.42”. What is the meaning of this statement in relation to speed of light? [Delhi] -Chemistry-10

Description : 6. “The refractive index of diamond is 2.42”. What is the meaning of this statement in relation to speed of light? [Delhi] -Chemistry-10

Last Answer : Answer. hope this helps you

5. The refractive indices of four media A, B, C and D are given in the following table: -Chemistry-10

Description : 5. The refractive indices of four media A, B, C and D are given in the following table: -Chemistry-10

Last Answer : (i) Minimum change is seen as light moves between 1.50 and 1.52, i.e. B and C. (ii) Maximum change when light moves between 1.33 and 2.40, i.e. A and D.

4. If a light ray IM is incident on the surface AB as shown, identify the correct emergent ray. [Delhi (C)] -Chemistry-10

Description : 4. If a light ray IM is incident on the surface AB as shown, identify the correct emergent ray. [Delhi (C)] -Chemistry-10

Last Answer : Answer. Ray NQ, as it has to be parallel to ray OS.

3. Draw the ray diagram in each case to show the position and nature of the image formed when the object is placed: -Chemistry-10

Description : 3. Draw the ray diagram in each case to show the position and nature of the image formed when the object is placed: -Chemistry-10

Last Answer : Answer. Nature of image: Real, inverted and same size image is formed at the centre of curvature. Nature of image: Virtual, enlarged and erect image is formed behind the mirror. Nature of image: ... image: Virtual, erect and diminished image is formed between O and F on the same side of object.

2. An object 50 cm tall is placed on the principal axis of a convex lens. Its 20 cm tall image is formed on the screen placed at a distance of 10 cm from the lens. Calculate the focal length of the lens. [All India] -Chemistry-10

Description : 2. An object 50 cm tall is placed on the principal axis of a convex lens. Its 20 cm tall image is formed on the screen placed at a distance of 10 cm from the lens. Calculate the focal length of the lens. [All India] -Chemistry-10

Last Answer : this is the answer for the respected question

1. A concave lens has focal length of 20 cm. At what distance from the lens a 5 cm tall object be placed so that it forms an image at 15 cm from the lens? Also calculate the size of the image formed. [Delhi] -Chemistry-10

Description : 1. A concave lens has focal length of 20 cm. At what distance from the lens a 5 cm tall object be placed so that it forms an image at 15 cm from the lens? Also calculate the size of the image formed. [Delhi] -Chemistry-10

Last Answer : Answer. hope this helps youu

What happens when a substance gains oxygen during reaction? The substance gets – (a) Oxidised (b) Reduced (c) Both oxidized and reduced (d) None of the above

Description : What happens when a substance gains oxygen during reaction? The substance gets – (a) Oxidised (b) Reduced (c) Both oxidized and reduced (d) None of the above

Last Answer : (a) Oxidised

Copper substances when exposed to air gains a green coating due to the formation of: (1) CuO (2) CuCO3 Cu(OH)2 (3) CuSO4 (4) Cu(NO3)2

Description : Copper substances when exposed to air gains a green coating due to the formation of: (1) CuO (2) CuCO3 Cu(OH)2 (3) CuSO4 (4) Cu(NO3)2

Last Answer : (2) CuCO3 Cu(OH)2 Explanation: When copper is exposed to air, it reacts with moist carbon dioxide in the air and slowly loses its shiny brown surface and gains a green coat. This green substance is ... Cu(OH)2). The formation of this green coating on the surface of a copper object corrodes it.

What happens when a substance loses oxygen during reaction? It is said to be (a) Oxidised (b) Reduced (c) Both (d) None of the above

Description : What happens when a substance loses oxygen during reaction? It is said to be (a) Oxidised (b) Reduced (c) Both (d) None of the above

Last Answer : (b) Reduced

Identify the type of reaction(s) in the following equations. (i)CH4 + 2O2 CO2 + 2 H2O (ii) Pb(NO3)2 + 2KI ——–>Pbl2 + 2KNOs (iii) CaO + H2O ——–> Ca(OH)2 (iv) CuSO4 + Zn ——–> ZnSO4 + Cu -Chemistry

Description : Identify the type of reaction(s) in the following equations. (i)CH4 + 2O2 CO2 + 2 H2O (ii) Pb(NO3)2 + 2KI ——–>Pbl2 + 2KNOs (iii) CaO + H2O ——–> Ca(OH)2 (iv) CuSO4 + Zn ——–> ZnSO4 + Cu -Chemistry

Last Answer : Answer. (i) Combustion reaction and oxidation reaction. (ii)Double displacement reaction and precipitation reaction. (iii) Combination reaction. (iv) Displacement reaction.

Assertion :- `H_(2)S+Cl_(2)rarr2HCl+S` In the above reaction, Cl has been oxidised to `Cl^(-)` while `S^(-2)` has been reduced to S Reason :- In a rea

Description : Assertion :- `H_(2)S+Cl_(2)rarr2HCl+S` In the above reaction, Cl has been oxidised to `Cl^(-)` while `S^(-2)` has been reduced to S Reason :- In a rea

Last Answer : Assertion :- `H_(2)S+Cl_(2)rarr2HCl+S` In the above reaction, Cl has been oxidised to `Cl^(-)` ... is False. D. If both Assertion & Reason are False.

Silver halides are used in photographic plates because they are (a) Oxidised in air (b) Colourless (c) Easily soluble in a hypo solution (d) Readily reduced by light

Description : Silver halides are used in photographic plates because they are (a) Oxidised in air (b) Colourless (c) Easily soluble in a hypo solution (d) Readily reduced by light

Last Answer : Ans:(d)

Silver halides are used in photographic plates because they are - (1) oxidised in air (2) soluble in hyposolution (3) reduced by light (4) totally colourless

Description : Silver halides are used in photographic plates because they are - (1) oxidised in air (2) soluble in hyposolution (3) reduced by light (4) totally colourless

Last Answer : (3) reduced by light Explanation: The light-sensitive chemicals used in photographic film and paper are silver halides. Silver halides are used in photographic film and photographic paper, including ... - meaning that it can undergo development which turns the entire crystal into metallic silver.

When iron is rusted, it is (A) Converted to a fine powder (B) Reduced (C) Oxidised (D) None of these

Description : When iron is rusted, it is (A) Converted to a fine powder (B) Reduced (C) Oxidised (D) None of these

Last Answer : (C) Oxidised

Silver halides are used in photographic plates because they are (1) oxidised in air (2) soluble in hyposolution (3) reduced by light (4) totally colourless

Description : Silver halides are used in photographic plates because they are (1) oxidised in air (2) soluble in hyposolution (3) reduced by light (4) totally colourless

Last Answer :  reduced by light

Among the metals Na,Mg ,Al,Zn,Cu,Sn ,Fe and Pb number of metals that can be ectreated by the eletroysis ,even from aqueos solution,is………………….

Description : Among the metals Na,Mg ,Al,Zn,Cu,Sn ,Fe and Pb number of metals that can be ectreated by the eletroysis ,even from aqueos solution,is………………….

Last Answer : Among the metals Na,Mg ,Al,Zn,Cu,Sn ,Fe and Pb number of metals that can be ectreated by the eletroysis ,even from aqueos solution,is………………….

Number of metals among following which are obatained by electromentallurgy in molten state are Li, Ba, Na,Al, Fe, Cu, Pb, Sn, Ag, Zn, Ca, Mg.

Description : Number of metals among following which are obatained by electromentallurgy in molten state are Li, Ba, Na,Al, Fe, Cu, Pb, Sn, Ag, Zn, Ca, Mg.

Last Answer : Number of metals among following which are obatained by electromentallurgy in molten state are Li, Ba, Na,Al, Fe, Cu, Pb, Sn, Ag, Zn, Ca, Mg.

Gastric lipae is activated in the presence of (A) Bile salts (B) Cu++ (C) K+ (D) Na+

Description : Gastric lipae is activated in the presence of (A) Bile salts (B) Cu++ (C) K+ (D) Na+

Last Answer : Answer : A

Which of the following can be purified by the electrolytic method? (a) Sodium (Na) (b) Copper (Cu) (c) Boron (B) (d) Chlorine (C12)

Description : Which of the following can be purified by the electrolytic method? (a) Sodium (Na) (b) Copper (Cu) (c) Boron (B) (d) Chlorine (C12)

Last Answer : Ans:129

The deficiencies of micronutrients, not only affect growth of plants but also vital functions such as photosynthetic and mitochondrial electron flow. Among the list given below, which group of three elements shall affect most, both photosynthetic and mitochondrial electron transport?(a) Co, Ni, Mo (b) Ca, K, Na (c) Mn, Co, Ca (d) Cu, Mn, Fe

Description : The deficiencies of micronutrients, not only affect growth of plants but also vital functions such as photosynthetic and mitochondrial electron flow. Among the list given below, which group of three elements shall affect most, both ... , Mo (b) Ca, K, Na (c) Mn, Co, Ca (d) Cu, Mn, Fe

Last Answer : d) Cu, Mn, Fe

(a) What are fuel cells? Explain the electrode reactions involved in the working of H2 – O2 fuel cell. (b) Represent the galvanic cell in which the reaction Zn (s) + Cu2+ (aq) → Zn2+ (aq) + Cu (s) takes place. -Chemistry

Description : (a) What are fuel cells? Explain the electrode reactions involved in the working of H2 – O2 fuel cell. (b) Represent the galvanic cell in which the reaction Zn (s) + Cu2+ (aq) → Zn2+ (aq) + Cu (s) takes place. -Chemistry

Last Answer : (a) Fuel cells : These cells are the devices which convert the energy produced during combustion of fuels like H2, CH4, etc. directly into electrical energy. The electrode reaction for H2 – O2 fuel cell : (b) The galvanic cell may be represented as Zn (s) | Zn2+ (1M) || Cu2+ (1M) | Cu (s)

Calculate the number of Cu atoms in 0.635g of Cu. -Chemistry

Description : Calculate the number of Cu atoms in 0.635g of Cu. -Chemistry

Last Answer : No. of moles of Cu = Mass of Cu/Atomic mass = 0.635/63.5 =0.01 mole No. of Cu atoms = No. of moles × Avogadro constant = 0.01 × 6.022 × 1023 = 6.022 × 1023 Cu atoms.

Substances containing all the four elements: carbon, hydrogen nitrogen and oxygen are 1. Morphine 2. Nucleic acids 3. Starch 4. Quinine Select the correct answer by using the code below, (a) 2, 3 and 4 only (b) 1, 2 and 4 only (c) 1, 2, 3 and 4 (d) 1, 2 and 3 only

Description : Substances containing all the four elements: carbon, hydrogen nitrogen and oxygen are 1. Morphine 2. Nucleic acids 3. Starch 4. Quinine Select the correct answer by using the code below, (a) 2, 3 and 4 only (b) 1, 2 and 4 only (c) 1, 2, 3 and 4 (d) 1, 2 and 3 only

Last Answer : Ans:(b)

If the impurity in a metal has a greater affinity for oxygen and is more easily oxidised than the metal, then the purification of metal may be carried

Description : If the impurity in a metal has a greater affinity for oxygen and is more easily oxidised than the metal, then the purification of metal may be carried

Last Answer : If the impurity in a metal has a greater affinity for oxygen and is more easily oxidised than ... B. electrorefining C. Zone refining D. POILING

To test chemical oxygen demand (C.O.D.) of sewage, organic matter is oxidised by potassium dichromate in the presence of A. Hydrochloric acid B. Sulphuric acid C. Nitric acid D. Citric acid

Description : To test chemical oxygen demand (C.O.D.) of sewage, organic matter is oxidised by potassium dichromate in the presence of A. Hydrochloric acid B. Sulphuric acid C. Nitric acid D. Citric acid

Last Answer : ANS: B

Pick up the correct statement from the following: (A) In basic Bessemer process, the steel heats the converter (B) In open-hearth process, the furnace heats the steel (C) In Siemens process, the impurities of pig iron are oxidised by the oxygen of the ore (D) All the above

Description : Pick up the correct statement from the following: (A) In basic Bessemer process, the steel heats the converter (B) In open-hearth process, the furnace heats the steel (C) In Siemens process, the impurities of pig iron are oxidised by the oxygen of the ore (D) All the above

Last Answer : Answer: Option D

State the type of chemical reactions and chemical equations that take place in the following: (i) Magnesium wire is burnt in air. (ii) Electric current is passed through water. (iii) Ammonia and hydrogen chloride gases’are mixed. -Chemistry

Description : State the type of chemical reactions and chemical equations that take place in the following: (i) Magnesium wire is burnt in air. (ii) Electric current is passed through water. (iii) Ammonia and hydrogen chloride gases’are mixed. -Chemistry

Last Answer : This is the Answer:

Carrier ions like Na+ facilitate the absorption of substances like (a) amino acids and glucose (b) glucose and fatty acids (c) fatty acids and glycerol (d) fructose and some amino acids.

Description : Carrier ions like Na+ facilitate the absorption of substances like (a) amino acids and glucose (b) glucose and fatty acids (c) fatty acids and glycerol (d) fructose and some amino acids.

Last Answer : (a) amino acids and glucose

What weight of Na will contain the same number of atoms as are present in 2.4 gm of carbon? -Chemistry 9th

Description : What weight of Na will contain the same number of atoms as are present in 2.4 gm of carbon? -Chemistry 9th

Last Answer : 1 mole of Carbon has weight 12g. So 0.2 mole of Carbon will have weight 2.4 g. Now, 1 mole of Carbon contains 6.022 10^23 atoms So 0.2 moles of Carbon contains 1.2044 10^23 atoms. So we need to find the weight ... of Na. 1 mole of Na = 23 g So 0.2 mole of Na = 4.6 grams So, answer is 4.6 grams.

How many compound(s) or iron (s) can be oxidised by `H_(2)O_(2)` among the following (i) `AsO_(3)^(2)` (ii) `SO_(4)^(2-)` (iii) `Fe_(2) (SO_(4))_(3)`

Description : How many compound(s) or iron (s) can be oxidised by `H_(2)O_(2)` among the following (i) `AsO_(3)^(2)` (ii) `SO_(4)^(2-)` (iii) `Fe_(2) (SO_(4))_(3)`

Last Answer : How many compound(s) or iron (s) can be oxidised by `H_(2)O_(2)` among the following (i) `AsO_(3)^(2)` (ii) ... ` (v) `H_(2)S` (vi) PbS (vii) `O_(3)`

How many compound(s) or iron (s) can be oxidised by `H_(2)O_(2)` among the following (i) `AsO_(3)^(2)` (ii) `SO_(4)^(2-)` (iii) `Fe_(2) (SO_(4))_(3)`

Description : How many compound(s) or iron (s) can be oxidised by `H_(2)O_(2)` among the following (i) `AsO_(3)^(2)` (ii) `SO_(4)^(2-)` (iii) `Fe_(2) (SO_(4))_(3)`

Last Answer : How many compound(s) or iron (s) can be oxidised by `H_(2)O_(2)` among the following (i) `AsO_(3)^(2)` (ii) ... ` (v) `H_(2)S` (vi) PbS (vii) `O_(3)`