Chemistry

1. A compound has molecular mass 110.15 g mol⁻¹ and empirical formula C₃H₃O. Its molecular formula will be

(Note: Molar mass of C = 12 g mol⁻¹, O = 16 g mol⁻¹ and H = 1 g mol⁻¹)

2. In a calorimeter, 13.3 moles of water are used to measure the heat of combustion from 0.303 g of sugar (C₁₂H₂₂O₁₁). The specific heat capacity of water is 4.2 JK⁻¹g⁻¹ and the rise in temperature is recorded as 5.0 K.

(Note: Molar masses of water and sugar are 18.0 g/ mol and 342.3 g/ mol respectively.)

The amount of heat evolved during combustion of 1.0 mol of sugar would be

3. The depression in freezing point (ΔTf) is directly proportional to

4. All of the following observations exemplifies the use of quantitative science EXCEPT a/an

5. The standard cell potential of a voltaic cell that uses the Ag/Ag⁺ and Sn/Sn²⁺ half-cell reactions is

Note: E° Ag = + 0.80 V and E° Sn = − 0.14 V)

6. Consider the following reaction.

2Al(s) + 6HBr(aq) → 2AlBr3(s) + 3H2(g)

How many moles of H2 are produced when 1.61 moles of Al react with 2.48 moles of HBr?

7. The oxidation number of oxygen in Cs₂O is

(Note: Cs¹³³₅₅and O¹⁶₈ )

8. The given reaction is an example of

9. On a Kelvin scale, the temperature of 23℉ is equal to

10. The amount of heat required to raise the temperature of one gram of a substance by one Kelvin is called

11. The given equation represents the synthesis of ammonia gas.

N₂(g) + 3H₂(g) ⇌ 2NH₃(g)

If the value of equilibrium constant (Kc) at 500ºC is 6.0 × 10⁻², and the general gas constant (R) is 0.0821 dm³.atm.K⁻¹.mol⁻¹, then the value of Kp for this reaction will be

12. Read the given properties.

1. Flows like pure liquids
2. Exhibits symmetry like crystalline solids
3. Shows greater mobility than ordinary liquids
4. Possesses more organised structure than crystalline solids

The properties that describe a liquid crystal are

13. Which of the following conditions were applied in the discharge tube to study the production of cathode rays?

14. Which of the following sets of quantum numbers CORRECTLY represents the position of an unpaired electron in 3d orbital?

15. NaCl and CsF have the same geometry because the

16. Raising the temperature of a gas in a closed system increases the average kinetic energy because the

17. A gas deviates from its ideal behaviour at a greater

18. The number of moles in 4.8 × 10²⁴ atoms of helium is

(Note: ⁴₂He)

19. The momentary force of attraction created between instantaneous dipole and induced dipole is called

20. Blood and paints are classified as sol because the dispersed phase and dispersion medium in these colloidal systems are

21. Consider the given ions.

• NH₄⁺ ions
• Cl⁻ ions
• OH⁻ ions

The addition of NH₄Cl in an aqueous solution of NH₄OH will suppress the concentration of

22. Consider the following values of quantum numbers.

• Principal quantum number (n) = 2
• Azimuthal quantum number (l) = n–1
• Magnetic quantum number (m) = –l, 0, +l

Based on the given information, the designated position of an electron is

23. The amount of energy required to convert one mole of a solid directly into a gas at constant pressure is termed as

24. The reaction between HCl and KMnO₄ in an acidic medium gives the following half reactions.

Oxidation half reaction: 2Cl⁻(aq) → Cl₂(g)

Reduction half reaction: MnO₄⁻(aq) → Mn²⁺(aq)

What should be added on the left hand side (L.H.S.) and the right hand side (R.H.S.) of the equation to balance the reduction half reaction?

25. In the discharge tube experiment, X-rays are produced when rapidly moving electrons strike with the

26. In the given energy diagram, the activation energy of the reaction in the presence of catalyst (CuCl₂) is represented by

27. To convert from Coulombs to Faraday, the value must be

28. Hydrolysis of a salt yields Ca(OH)₂ and HCl. The nature of this hydrolysed salt is

29. Which of the following molecules has a net dipole moment of zero

30. Given that 2A + B → 2C has the order with respect to A = 2 and the order overall = 3.

What will be the rate law expression for this reaction?

31. The bond energy values of HF > HCl > HBr > HI.

This decreasing trend is observed because when moving from HF to HI the

32. The INCORRECT description about cathode rays is that they

33. Long chains of amino acids can form helix by

34. The given crystal system can be identified as

35. Consider the given reaction.

OF₂₍𝓰₎ + H₂O₍ₗ₎ → 2HF₍𝓰₎ + O₂₍𝓰₎

The substance that acts as an oxidising agent in the given reaction is

36. Below are the thermochemical reactions for the oxidation of carbon and carbon monoxide with the associated enthalpy changes.

Based on the given information, the enthalpy of combustion for carbon forming carbon dioxide will be

37. A molecule of chlorine is formed by the overlapping of

38. Platinum is used as a catalyst in the manufacturing of sulphuric acid by the contact process. In this process, platinum can become ineffective if it

39. Water boils at low temperature when there is low

40. Lattice energy of an ionic compound increases and becomes more negative when

41. The two different crystalline forms of CaCO3 are

42. In a gas discharge tube, the factors on which voltage depends are the

1. length of the tube
2. pressure inside the tube
3. type of gas inside the tube
4. type of metallic electrodes used

43. Given are the standard enthalpy changes for the series of reactions occurring in the formation of lithium fluoride (LiF).

The lattice energy of LiF is

44. The number of bromide ions in 3.5 moles of MgBr₂ is

(Note: Atomic mass of Br = 79.904 ≈ 80 amu)

45. K₂SO₄ and K₂CrO₄ are isomorphs with orthorhombic crystalline forms because they both have the same

46. The solubility of barium sulphate (BaSO₄) at 298 K is 1.05 x 10⁻⁵ mol dm⁻³.

Based on the given information, the solubility product of BaSO₄ will be

47. The given graph shows the change in the concentrations of reactants and products as the reaction 2SO₂(g) + O₂(g) ⇌ 2SO₃(g) approaches equilibrium.

In this graph, equilibrium is reached at point

48. In the given reaction, the reactant H2O can be classified as a/ an

49. The vapour pressure of ethyl ether at 20°C is 442.2 torr while that of water is 43.9 torr. The vapour pressure of water is less because water has

50. The average enthalpy required to break different bonds of same type within a molecule in a
sequential manner is known a

1. A scientist uses 52 g of Na₂SO₄ for a chemical reaction.

How many moles of Na atoms does the compound contain?

(Note: Molar mass of Na = 23 g mol⁻¹, S = 32 g mol⁻¹ and O = 16 g mol⁻¹)

2. If a mixture of 7 cm³ of CH₄ and 7 cm³ of C₂H₄ is burnt, then the volume of oxygen required for their complete combustion is

3. In PCl₅, the percentage of chlorine atoms by mass is

(Note: ³¹₁₅P and ³⁵-⁵₁₇Cl)

4. The use of a balanced chemical equation to calculate the amount of product that will form during a chemical reaction gives the

5. The oxidation number of sulphur in SO₃²⁻ is

6. An example of disproportionation redox reaction in which the same element is oxidised as well as reduced is

7. Consider the following redox reaction in an aqueous medium.

Fe⁺² + Ag⁺ → Fe⁺³ + Ag

The standard reduction potential values for iron and silver are +0.77 V and +0.80 V, respectively.

The overall cell potential and the feasibility of the reaction will be

8. To convert from Coulombs to Faraday, the value must be

9. During the discovery of electrons, a glow is produced inside the discharge tube. The colour of glow depends on the

10. In a gas discharge tube, the factors on which voltage depends are the

1. length of the tube
2. pressure inside the tube
3. type of gas inside the tube
4. type of metallic electrodes used

11. The given image shows the different spectral lines of hydrogen atom.

In the given image, Paschen series is labelled as

12. Which of the following sets of quantum numbers CORRECTLY represents the position of an unpaired electron in 3d orbital?

13. A molecule of water is a polar compound because it

14. The molecular geometry of phosphorus trichloride, PCl₃, is trigonal pyramidal.

According to its shape, how many bond pairs and lone pairs are present in PCl₃?

15. The type of magnetism depicted by O₂⁺² is

16. Consider the given structure of boron trifluoride (BF₃) molecule.

The type of orbital overlap labelled as X is

17. How many sigma and pi bonds are present in a molecule of C₂H₂?

18. Raising the temperature of a gas in a closed system increases the average kinetic energy because the

19. The maximum density of water occurs at 277 Kelvin and 1 atmospheric pressure.

The approximate temperature in the Fahrenheit scale will be

(Note: 0°C = 273.15 K)

20. How much pressure in Nm⁻² is exerted by one mole of a gas enclosed in a vessel of volume 59.4 m³ at 120°C?

(Note: R = 8.314 JK⁻¹mol⁻¹)

21. To avoid a pressure related injury during ascent, a scuba diver must equalise the pressure by

22. A gas deviates from its ideal behaviour at a greater

23. Surface area is the property of liquids that depends on the

24. At 4°C, water has a tendency to exhibit maximum

25. The boiling points of diethyl ether and ethyl alcohol are 34.6ºC and 78.5ºC, respectively.

Comparatively, the low boiling point of diethyl ether indicates that it has

26. The amount of energy required to convert one mole of a solid directly into a gas at constant pressure is termed as

27. Read the given properties.

1. Flows like pure liquids
2. Exhibits symmetry like crystalline solids
3. Shows greater mobility than ordinary liquids
4. Possesses more organised structure than crystalline solids

The properties that describe a liquid crystal are

28. All of the following materials exhibit variations in physical properties along different molecular axes EXCEPT

29. In crystallography, if properties of a crystal vary with the change in direction, then this feature is identified as

30. All of the following pairs of substances are polymorphs EXCEPT

31. Given is the crystal lattice of sodium chloride.

The MAIN factor(s) that contribute(s) to the lattice energy of this crystal lattice is/ are

1. the size of the ions.
2. the charge on the ions.
3. the size of the crystal.

32. The simplest and the least volume consuming repeating structure of any solid is known as a/ an

33. A TRUE statement about the effect of catalyst is that it

34. The equilibrium constant KP for the given reaction can be expressed as

CaCO₃(s) ⇌ CaO(s) + CO₂(g)

35. The solubility product (Ksp) of BaSO₄ is 1.08 × 10⁻¹⁰ at 25°C.

If 10.0 mL solution of 2.0 × 10⁻³ M Na₂SO₄ is added to 100 mL solution of 3.2 × 10⁻⁴ M BaCl₂, then BaSO₄ will precipitate out because the

36. Which of the following elements forms an amphoteric as well as normal oxide?

37. If the pH of bleach is 12.6, then the concentration of hydrogen ions in this solution is

38. A basic buffer is prepared by mixing a weak base and a salt of

39. Hydrolysis of a salt yields Ca(OH)₂ and HCl. The nature of this hydrolysed salt is

40. The presence of electric charge on colloidal particles can be observed through

41. If 2.5 grams of (NH₂)₂CO is dissolved in water to prepare 100 cm3 solution, the molarity of the solution will be

(Note: ¹²₆C, ¹₁H, ¹⁶₈O and ¹⁴₇N)

42. What happens when a non-volatile solute is added to a pure solvent?

43. Toothpaste is an example of a colloidal solution because its particles

44. The given reaction is an example of

45. Platinum is used as a catalyst in the manufacturing of sulphuric acid by the contact process. In this process, platinum can become ineffective if it

46. The labelled part in the given energy diagram that represents the minimum energy required for the enzyme catalysed reaction is

47. In which of the following reactions does a non-spontaneous reaction occur?

48. Mathematically, the first law of thermodynamics is expressed as

49. If the enthalpy of combustion for graphite to form carbon dioxide is –393.7 kJ mol⁻¹ and that for carbon monoxide to form carbon dioxide is –283 kJ mol⁻¹ , then what will be the enthalpy of formation for carbon monoxide as per the given reaction?

C(s) + ½O₂(g) → CO(g)

50. An electrical energy of 7.52 J is passed through a calorimeter, increasing its temperature from 0.10 K to 2.5 K.

The heat capacity of the calorimeter will be

1. The given chemical equation shows a reaction of chlorine with cold, dilute solution of sodium hydroxide.

Cl₂(g) + 2NaOH(aq) → NaCl(aq) + NaClO(aq) + H₂O(l)

How many grams of sodium hydroxide will be used to synthesise 6 moles of sodium chlorate(I)?

(Note: Molar mass of Na = 23 g mol⁻¹, Cl = 35.5 g mol⁻¹, H = 1 g mol⁻¹ and O = 16 g mol⁻¹)

2. The number of moles in 4.8 × 10²⁴ atoms of helium is

(Note: ⁴₂He)

3. The percentage by mass of carbon in (CH3)2CO is

(Note: Molar mass of C = 12 g mol⁻¹, H = 1 g mol⁻¹ and O = 16 g mol⁻¹)

4. A compound has molecular mass 110.15 g mol⁻¹ and empirical formula C₃H₃O. Its molecular formula will be

(Note: Molar mass of C = 12 g mol⁻¹, O = 16 g mol⁻¹ and H = 1 g mol⁻¹)

5. The oxidation number of nitrogen in [Cu(NH₃)₄]²⁺ is

6. The reaction between HCl and KMnO₄ in an acidic medium gives the following half reactions.

Oxidation half reaction: 2Cl⁻(aq) → Cl₂(g)

Reduction half reaction: MnO₄⁻(aq) → Mn²⁺(aq)

What should be added on the left hand side (L.H.S.) and the right hand side (R.H.S.) of the equation to balance the reduction half reaction?

7. Which of the following daily life chemical reactions does NOT exemplify a redox reaction?

8. The standard cell potential of a voltaic cell that uses the Ag/Ag⁺ and Sn/Sn²⁺ half-cell reactions is

Note: E° Ag = + 0.80 V and E° Sn = − 0.14 V)

9. Which of the following conditions were applied in the discharge tube to study the production of cathode rays?

10. The amount of energy associated with a quantum of radiation is

11. In the discharge tube experiment, X-rays are produced when rapidly moving electrons strike with the

12. The quantum number representing the energy level in which the electron revolves around the nucleus is called

13. The bond energy values of HF > HCl > HBr > HI.

This decreasing trend is observed because when moving from HF to HI the

14. The CORRECT order for the decrease in repulsion between electron pairs is

15. Compared to the valence bond theory, the molecular orbital theory

16. A molecule of chlorine is formed by the overlapping of

17. The option that CORRECTLY relates bond order to the types of bonds in a nitrogen molecule is

(Note: ¹⁴₇N)

18. According to Charles’s Law, what will happen if a blown balloon is left inside a car at noon on a hot summer day?

19. If four flasks contain same number of molecules of a gas at room temperature, then which flask will have the HIGHEST pressure?

20. On a Kelvin scale, the temperature of 23℉ is equal to

21. The density of a substance is directly proportional to its molar mass. If the density, temperature and pressure are known, then the molar mass of the substance can be calculated.

This information is TRUE if the substance at standard temperature and pressure is a

22. Gases are non-ideal at low temperature because the molecules of gases have

23. The momentary force of attraction created between instantaneous dipole and induced dipole is called

24. Long chains of amino acids can form helix by

25. The vapour pressure of ethyl ether at 20°C is 442.2 torr while that of water is 43.9 torr. The vapour pressure of water is less because water has

26. Liquid crystal is a state of matter which is in between

27. The statement that BEST describes the relationship between energy and intermolecular forces is that

28. A student studied electrical conductivity in four different substances. He found one of these substances to be anisotropic as it showed greater electrical conductivity in one direction than in another.

Based on his study, the anisotropic substance must be

29. K₂SO₄ and K₂CrO₄ are isomorphs with orthorhombic crystalline forms because they both have the same

30. The two different crystalline forms of CaCO3 are

31. The given crystal system can be identified as

32. NaCl and CsF have the same geometry because the

33. What will be the effect on the equilibrium constant when the concentration of the reactants is doubled in a reversible reaction?

34. In 1 dm³ container, 3 moles of N₂O₄(g) and 1.5 moles of NO₂(g) are placed to give the following reaction.

N₂O₄(g) ⇋ 2NO₂(g)                                                                                                                        KC = 0.36 at 25°C

Which of the following conditions is CORRECT for the reaction to achieve equilibrium?

35. Consider the given equilibrium system.

CO₂(g) + H₂(g) ⇌ H₂O(g) + CO(g)

If the equilibrium is to be shifted in the reverse direction, then the two stresses that must be applied on this system are

36. Which of the following relationships is INCORRECT?

37. In a reaction between hydrogen sulphide gas (H₂S) and water (H₂O), H₂S acts as a

38. A 100 cm³ of aqueous solution of Fe₂(SO₄)₃ is prepared by dissolving 2 g of it in water.

The concentration of SO₄²⁻ ions in this solution is

(Note: The molecular mass of Fe₂(SO₄)₃ is 400 g mol⁻¹.)

39. Consider the given solubility equilibrium.

NH₃(g) + H₂O(l) ⇌ NH₄⁺(aq) + OH⁻(aq)

The Kb expression for this reaction would be

40. Blood and paints are classified as sol because the dispersed phase and dispersion medium in these colloidal systems are

41. In cryoscopy, the formula for finding molar (molecular) mass of a solute is

Note:

M₂ = Molar mass of solute
∆Tf = Depression in freezing point
Kf = Molal freezing point constant
W₁ = Mass of solvent in kg
W₂ = Mass of solute

42. The Raoult equation that shows the quantitative relationship between relative lowering of vapour pressure and mole fraction of solute is

43. The depression in freezing point (ΔTf) is directly proportional to

44. The given reaction is an example of

45. Given that 2A + B → 2C has the order with respect to A = 2 and the order overall = 3.

What will be the rate law expression for this reaction?

46. In the given energy diagram, the activation energy of the reaction in the presence of catalyst (CuCl₂) is represented by

47. The sum of kinetic energies and potential energies of the molecules constituting the system as a whole (and not of individual molecule) is termed as

48. Lattice energy of an ionic compound increases and becomes more negative when

49. Consider the given reaction with a negative enthalpy.

H₂(g) + Cl₂(g) → 2HCl(g)           ∆H = −184 kJ mol⁻¹

In this reaction, the negative sign indicates that

50. The amount of heat required to raise the temperature of one gram of a substance by one Kelvin is called

1. Consider the following reaction.

2Al(s) + 6HBr(aq) → 2AlBr3(s) + 3H2(g)

How many moles of H2 are produced when 1.61 moles of Al react with 2.48 moles of HBr?

2. The type of stoichiometric calculations that does NOT require the use of molar mass is

3. The set of quantities conserved in every chemical reaction are

4. The FIRST step to calculate the empirical formula of a new compound is to determine the

5. In a laboratory, Zafar synthesised a 13.2 g sample of C₉H₈O₄ (aspirin) by using 11.9 g of C₇H₆O₃

If the expected yield of aspirin is 15.52 g, then the % yield that he will obtain is

6. All of the following observations exemplifies the use of quantitative science EXCEPT a/an

7. The electronic configuration of calcium ion in CaCl₂ is

8. The spectral lines of X series are produced in Y region when an electron jumps from n = 5 to n = 3 energy level

Based on the given information, the X series and Y region are represented as

9. According to Hund’s rules, the CORRECT way of arranging the electrons in ‘p’ orbitals is

10. Consider the following values of quantum numbers.

• Principal quantum number (n) = 2
• Azimuthal quantum number (l) = n–1
• Magnetic quantum number (m) = –l, 0, +l

Based on the given information, the designated position of an electron is

11. In a discharge tube, a gas can conduct electricity at X pressure and Y voltage

The conditions X and Y are identified as

12. The INCORRECT description about cathode rays is that they

13. The average enthalpy required to break different bonds of same type within a molecule in a
sequential manner is known a

14. The ionic character in a covalent molecule is due to its

15. Which of the following molecules has a net dipole moment of zero

16. The shape that shows the head-on overlapping between hybrid orbitals is

17. Valence bond theory explains the

18. Glucose is readily soluble in water because it

19. When heat is provided to the liquid during a phase change, molecules tend to move from their
positions.

In the given situation, the impact of heat on the intermolecular forces and energy of the
molecules that are close together will be

20. At 4°C, water has a tendency to exhibit maximum

21. Ammonia dissolves in water due to the formation of

22. Which of these molecules can form a strong hydrogen bond with itself?

23. NaCl does NOT conduct electricity in solid state because the

24. Diamond and silicon carbide are insoluble in all solvents because of their

25. Consider the given table

The given unit cell is identified as

26. The substances that are isomorphs of each other are

27. The solubility of barium sulphate (BaSO₄) at 298 K is 1.05 x 10⁻⁵ mol dm⁻³.

Based on the given information, the solubility product of BaSO₄ will be

28. The given graph shows the change in the concentrations of reactants and products as the reaction 2SO₂(g) + O₂(g) ⇌ 2SO₃(g) approaches equilibrium.

In this graph, equilibrium is reached at point

29. Consider the following endothermic reaction at equilibrium.

CaCO₃(s) ⇋ CaO(s) + CO₂(g)

What will be the effect when the given stresses are applied on the given reaction?

30. Consider the given ions.

• NH₄⁺ ions
• Cl⁻ ions
• OH⁻ ions

The addition of NH₄Cl in an aqueous solution of NH₄OH will suppress the concentration of

31. The given equation represents the synthesis of ammonia gas.

N₂(g) + 3H₂(g) ⇌ 2NH₃(g)

If the value of equilibrium constant (Kc) at 500ºC is 6.0 × 10⁻², and the general gas constant (R) is 0.0821 dm³.atm.K⁻¹.mol⁻¹, then the value of Kp for this reaction will be

32. Consider the given reaction that occurs at 400-450°C.

2SO₂(g) + O₂(g) ⇌ 2SO₃(g) ∆H = −196 kJ mol⁻¹

If the temperature of the given reaction is increased, then the amount of SO3(g) will

33. A solution is prepared for acid base titration by dissolving 10 g of NaOH in 100 g of water. The molality of this solution would be

(Note: Atomic mass of Na = 23 amu, O = 16 amu, H = 1 amu)

34. A basic buffer is prepared by mixing a weak base and a salt of

35. In the given reaction, the reactant zinc ion can be classified as a / an

Zn²⁺(aq) + 4NH₃(aq) ⇌ [Zn(NH₃)₄]²⁺(aq)

36. If the pH of a solution is 10, then the hydroxide ion concentration in the solution will be

37. A solution shows a reading of 7.21 on a pH meter. This indicates that the solution is a

38. The relationship between the acid dissociation constant (Ka) and the base dissociation constant (Kb) is represented as

39. In a bomb calorimeter, the enthalpy of combustion of a compound is measured at a constant

40. Consider the given data.

• 2NaOH(aq) + CO₂(g) → Na₂CO₃(aq) + H₂O(l) ΔH = -89.08KJ
• NaHCO₃(aq) + NaOH(aq) → Na₂CO₃(aq) + H₂O(l) ΔH₂ = -41.02KJ
• NaOH(aq) + CO₂(g) → NaHCO₃(aq) ΔH₁ = ?

Based on the given data, the enthalpy change for the formation of NaHCO₃(aq) is

41. Consider the following steps of a Born-Haber’s cycle.

1. Formation of crystal lattice from sodium and chloride ion.
2. Formation of a chloride ion from a gaseous chlorine atom.
3. Formation of gaseous sodium metal from solid sodium metal.
4. Formation of a chlorine atom from a diatomic chlorine molecule.

The endothermic steps involved in the Born-Haber’s cycle of sodium chloride are

42. The lattice energy of ionic compounds decreases with the increase in size of cations or anions.
This happens because when the size of either ion increases, the

43. Which of the following statements is TRUE for the given reaction?

2Fe(s) + 3Cl₂(g) → 2FeCl₃(s)

44. A cell reaction will be spontaneous when

45. Which of the following statements is TRUE about the potential of an electrochemical cell?

46. During the electrolysis of molten sodium chloride, a charge of 9650 C is passed through the electrolytic cell. This indicates that the amount of chlorine gas (Cl2) liberated at the anode will be

(Note: Cl³⁵.⁵₁₇)

47. The oxidation number of oxygen in Cs₂O is

(Note: Cs¹³³₅₅and O¹⁶₈ )

48. In which of the following oxidation states does a manganese (Mn) containing compound acts as an oxidising agent only?

49. All of the given biological processes are examples of redox reaction EXCEPT

50. The given figure shows a Zn²⁺|Zn (E° = − 0.76 V) and Sn²⁺|Sn (E° = − 0.14 V) voltaic cell.

1. If the molecular mass of an organic compound is 60 amu and its empirical formula is CH2O, then its molecular formula will be

2. The number of bromide ions in 3.5 moles of MgBr₂ is

(Note: Atomic mass of Br = 79.904 ≈ 80 amu)

3. Which of the following does NOT signify quantitative analysis?

4. If ‘X’ g of C and ‘2X’ g of Mg contains the same number of atoms, i.e., 6.02×10²³, then X is equal to

5. How many grams of nitrogen is approximately present in every 100 g of ammonium sulphate (NH₄)₂SO₄?

(Note: ¹₁H, ¹⁴₇N, ¹⁶₈O, ³²₁₆S )

6. If 100 molecules of acetic acid are ionised into acetate and hydronium ions out of 1000 molecules, then the number of ions produced by the dissociation of 100 moles of acetic acid will be

7. The magnetic quantum number value(s) for 3d orbitals is/ are

8. In a discharge tube, the positive rays are produced when high speed electrons strike the

9. “It is impossible to determine the exact position and the momentum of a moving electron around the nucleus of an atom, simultaneously.”

This statement represents

10. Henry Moseley did a systematic study of X-rays in the year 1913. According to his study, Xrays of shorter wavelength can be generated by

11. The de-Broglie wavelength of particle CANNOT be calculated by

12. The CORRECT representation of 3d𝓏² atomic orbital is

13. Which of the following orbitals of oxygen hybridise to form four sp³ hybrid orbitals in water molecule?