Arrange α, β and γ rays in ascending order of their penetrating power. OR Which kind of nuclear reaction is the source of the sun’s energy?
α < β < γ ray.
OR
Fusion reaction is the source of the sun’s energy.
Question ID: 128
Uploaded on: September 15, 2024
Match the right column with the left column: [1 × 4]
Left Column
Right Column
1. An alkali metal
(a) F
2. An element whose anion accelerates the rusting of iron
(b) Fe
3. Extracted from haematite
(c) K
4. Most electronegative element
(d) Cl
Left Column | Right Column |
1. An alkali metal | (c) K |
2. An element whose anion accelerates the rusting of iron | (d) Cl |
3. Extracted from haematite | (b) Fe |
4. Most electronegative element | (a) F |
Question ID: 129
Uploaded on: September 15, 2024
What type of chemical bond is present in CaO?
An ionic bond is present in CaO.
Question ID: 130
Uploaded on: September 15, 2024
What is used as a cathode to electroplate silver over a copper spoon? OR Give an example of a compound whose aqueous solution is a weak electrolyte.
Silver (Ag) is used as the cathode to electroplate silver over a copper spoon.
OR
Acetic acid (CH3COOH).
Question ID: 131
Uploaded on: September 15, 2024
During electrolysis which electrode is called a cathode?
The electrode connected to the negative terminal of the battery is called a cathode.
Question ID: 132
Uploaded on: September 15, 2024
State one use of liquid ammonia. OR Write the formula of the precipitate formed when an aqueous ammonia solution is added to an aqueous solution of aluminium chloride.
One use of liquid ammonia is as a refrigerant in refrigeration systems.
OR
The formula of the precipitate formed when aqueous ammonia is added to an aqueous solution of aluminium chloride is Al(OH)3 (aluminium hydroxide).
Question ID: 133
Uploaded on: September 15, 2024
In the laboratory preparation of nitrogen, an aqueous solution of which compound is mixed with an aqueous solution of ammonium chloride and heated.
In the laboratory preparation of nitrogen, an aqueous solution of Sodium Nitrite (NaNO3) is mixed with an aqueous solution of ammonium chloride and heated.
Question ID: 134
Uploaded on: September 15, 2024
Write the IUPAC name CH3CH2CHO. OR Write the structural formula of a positional isomer of CH3CH2CH2OH.
Propanal or Propan-1-al.
OR
The structural formula of the positional isomer of CH3CH2CH2OH (1-propanol) is CH3CH(OH)CH3 (2-propanol).
Question ID: 135
Uploaded on: September 15, 2024
Mention one use poly (tetrafluoroethylene).
Used as a coating in non-stick cookware due to its hydrophobic and high heat-resistant properties.
Question ID: 136
Uploaded on: September 15, 2024
What is methane hydrate?
Methane hydrate is a solid compound consisting of methane molecules trapped within a lattice of ice-like water molecules.
Question ID: 137
Uploaded on: September 15, 2024
The pressure of a mixed mass of a gas at a temperature of 0°C is doubled while the volume is halved. What will be the final temperature of the gas? OR Under constant pressure, a mixed mass of a gas is heated from 0°C to 546°C. What is the ratio of the final volume of the gas with its initial volume?
P2 = 2P1, V2 = V1/2, T1 = 273 K
From the combined gas equation : P_1V_1\\over T_1=P_2V_2\\over T_2
or, P_1V_1\\over 273=2P_1V_1\\over 2 × T_2
T2 = 273 K
∴ Final temperature (T2) = O ºC
OR
Initial Temperature (T1) = 273 K,
Final Temperature (T2) = 273 + 546 = 819 K
From Charle\'s Law: V_1\\over T_1=V_2\\over T_2
⇒ V_1\\over 273=V_2\\over 819
⇒ V_2\\over V_1=819\\over 273
⇒ V2 : V1 = 3 : 1
Question ID: 138
Uploaded on: September 15, 2024
What is meant by the optical centre of a convex lens? OR Why does the Earth’s sky appear blue during the daytime?
If a ray of light passes through a Convex lens such that the direction of the emergent rays is parallel to the direction of the incident rays, then the path of the ray of light inside the lens intersects the principal axis at a particular point. This point is called the optical centre of the convex lens.
OR
The Earth's sky appears blue during the daytime because blue light from the Sun is scattered more than other colours due to its shorter wavelength. This scattering causes the sky to look predominantly blue to our eyes.
Question ID: 139
Uploaded on: September 15, 2024