Rocket - Propellant and Other Questions in English

(D) $H_2O_2$ is used as an oxidant for rocket fuel and has $90 \%$ concentration to be used in rockets.

(B) $TNT$ (trinitrotoluene) is mixed with $NH_4NO_3$ (ammonium nitrate) to form a highly explosive mixture known as amatol.
This mixture is more powerful and cost-effective for blasting purposes.

(B) Amatol is a highly explosive material made by mixing $TNT$ $(Trinitrotoluene)$ with $Ammonium \ nitrate$ $(NH_4NO_3)$.

(B) biliquid propellant consists of two separate components: a liquid fuel and a liquid oxidizer,which are stored in separate tanks and mixed in the combustion chamber to produce thrust. Therefore,the correct option is $(B)$.

(A) . $A$ hybrid propellant consists of a solid fuel and a liquid oxidizer to provide propulsion energy and the working substance.
For example,solid acrylic rubber and liquid $N_2O_4$ are used as a hybrid propellant system.

(A) Rocket propellants consist of a fuel and an oxidizer. $Liquid \ hydrogen$,$Kerosene$,and $Liquid \ hydrazine$ are commonly used as fuels in various rocket engines. $Liquid \ Helium$ $(He)$ is an inert gas and is not used as a fuel; it is typically used for pressurization or cooling purposes in cryogenic systems.

(B) Space rockets are propelled by the combustion of rocket propellants. $A$ rocket propellant is a substance used to produce thrust in rockets,consisting of a fuel and an oxidizer.

(C) The $PSLV$ (Polar Satellite Launch Vehicle) is a multi-stage rocket.
It utilizes a combination of solid and liquid propellants in its different stages.
Specifically,it uses composite solid propellants in the booster stages and liquid propellants (like $N_2O_4$ with $UDMH$ or $MMH$) in the liquid stages to achieve the required thrust and control.
Therefore,both $(A)$ and $(B)$ are used in different stages of the rocket.

(D) Rocket propellants are substances used to produce thrust in rockets.
Liquid hydrogen $(H_{2(l)})$ is used as a fuel.
Liquid oxygen $(O_{2(l)})$ is used as an oxidizer.
Hydrazine $(N_2H_{4(l)})$ is also used as a fuel.
Since all the given substances are used as rocket propellants,the correct answer is that none of these are excluded.

(C) The motion of a rocket is based on the principle of conservation of momentum,which is a direct consequence of $Newton's \ third \ law$ of motion. The exhaust gases are ejected at high velocity in the backward direction,which exerts an equal and opposite reaction force (thrust) on the rocket in the forward direction.

(D) space rocket requires a self-contained source of energy and oxygen because there is no atmosphere in space to support combustion.
Therefore,it uses a mixture of fuel and an oxidizer,collectively known as a $propellant$,to generate the thrust required for propulsion.

(A) Composite solid propellants are used in rocket engines. These consist of a fuel and an oxidizer. The fuel is typically a polymer like $Polyurethane$ or $polybutadiene$,and the oxidizer is an inorganic salt,most commonly $Ammonium \ perchlorate$ $(NH_4ClO_4)$.

(C) biliquid propellant consists of a liquid fuel and a liquid oxidizer stored separately.
$N_2O_4$ (dinitrogen tetroxide) acts as the liquid oxidizer and unsymmetrical dimethylhydrazine $(UDMH)$ acts as the liquid fuel.
These two are hypergolic,meaning they ignite spontaneously upon contact,making them an ideal biliquid propellant system for rockets.
Nitroglycerine and nitrocellulose form solid propellants (double-base propellants).
$N_2O_4$ with acrylic rubber is not a standard propellant combination.

(A) The $SLV-3$ (Satellite Launch Vehicle-$3$) rocket developed by India used a solid propellant system.
Specifically,it utilized a composite solid propellant based on hydroxyl-terminated polybutadiene $(HTPB)$.

(C) In rocket propellants,an oxidizer is required to support the combustion of fuel. $Nitric \ acid$ $(HNO_3)$ and $Liquid \ oxygen$ $(LOX)$ are both common oxidizers. However,in the context of standard chemistry curriculum,$Liquid \ oxygen$ is the most frequently cited example of an oxidizer used in liquid-propellant rockets,while $Nitric \ acid$ is also used in specific hypergolic systems. Given the standard options,$Liquid \ oxygen$ is the primary choice for high-performance rocket engines.

(C) mixture of nitrocellulose and nitroglycerine is known as a double-base propellant.
In this combination,both components act as fuel and oxidizer,providing the necessary energy for propulsion.

(C) In the context of rocket propulsion and propellant chemistry,the specific impulse ${I_s}$ is a measure of the efficiency of the propellant.
For a stable and effective rocket blast,the specific impulse must satisfy the condition ${I_s} \ge T_c^{1/2}$,where ${T_c}$ is the critical temperature of the combustion process.
Therefore,option $C$ is the correct relationship.

(C) Rocket propellants typically consist of a fuel and an oxidizer.
$H_{2(l)}$ (liquid hydrogen) is used as a fuel,$O_{2(l)}$ (liquid oxygen) is used as an oxidizer,and $N_2H_{4(l)}$ (hydrazine) is used as a fuel.
Methane is generally not used as a standard rocket propellant in the context of common chemical propellants discussed in chemistry curricula.
Therefore,the correct option is $C$.

(D) The correct answer is $(D)$.
$N_2O_4$ (Dinitrogen tetraoxide) is commonly used as an oxidizer in liquid-propellant rocket engines because it is hypergolic with many fuels and can be stored as a liquid at room temperature.

(C) The combination of $Liquid \ H_2$ and $Liquid \ O_2$ is widely used as a high-performance rocket propellant.
In this system,$Liquid \ H_2$ acts as the fuel and $Liquid \ O_2$ acts as the oxidizer.
The reaction is highly exothermic,providing the necessary thrust for the rocket.

(A) . Solid propellants or composite propellants are mixtures of polymeric binders (such as polyurethane or polybutadiene as fuel) and ammonium perchlorate as an oxidiser.
These are used in $SLV-3$ and $ASLV$ rockets.

(C) The specific impulse $(I_s)$ of a rocket propellant is a measure of the efficiency of the rocket engine.
It is directly proportional to the square root of the combustion chamber temperature $(T_c)$ and inversely proportional to the square root of the average molecular mass $(M)$ of the exhaust gases.
The relationship is given by $I_s \propto \sqrt{T_c/M}$.
Therefore,$I_s \propto \sqrt{T_c}$.

(C) In rocket propulsion,a propellant consists of a fuel and an oxidizer.
Liquid hydrogen $(H_2)$ acts as the fuel,and liquid oxygen $(O_2)$ acts as the oxidizer.
This combination is highly efficient and is commonly used in space launch vehicles.

(D) In solid rocket propellants,$NH_4ClO_4$ (Ammonium perchlorate) is used as an oxidizer. It provides the necessary oxygen for the combustion of the fuel.

(D) The $SLV-3$ rocket uses a solid composite propellant. In this propellant,polyurethane is used as the fuel and ammonium perchlorate is used as the oxidizer.

(A) Glycerol acts as an antifreeze agent for aviation fuel,preventing it from freezing at high altitudes where temperatures are extremely low.

(D) The reaction between $H_2O_2$ (hydrogen peroxide) and $N_2H_4$ (hydrazine) is highly exothermic and releases a large amount of energy in the form of hot gases ($N_2$ and $H_2O$ vapor).
This reaction is represented as: $N_2H_4(l) + 2H_2O_2(l) \rightarrow N_2(g) + 4H_2O(g)$.
Due to this high energy release,this mixture is effectively used as a rocket propellant.

(B) $BaSO_4 + ZnS$ is known as lithopone,which is used as a white pigment.
$NI_3$ (nitrogen triiodide) is a contact-sensitive explosive.
$N_2O_4$ is used as an oxidiser in liquid rocket propellants.
$KO_2$ (potassium superoxide) is used in space capsules and submarines to produce $O_2$ and remove $CO_2$.
Therefore,the correct matching is $A-4, B-1, C-2, D-3$.

(D) Dinitrogen tetroxide $N_2O_4$ is used as an oxidant with liquid propellant in rockets.

(D) Liquid hydrogen $(H_2)$ acts as a fuel and liquid oxygen $(O_2)$ acts as an oxidizer in rocket propulsion systems. The reaction $2H_2(l) + O_2(l) \rightarrow 2H_2O(g)$ releases a tremendous amount of energy,providing the necessary thrust for the rocket.

(D) Liquid rocket propellants often use $N_2O_4$ (dinitrogen tetroxide) as an oxidizer. It is a powerful oxidizing agent that reacts hypergolically with various fuels like hydrazine $(N_2H_4)$ or its derivatives,making it highly effective for space propulsion systems.

(A) Glycerol is added to aviation fuel because it acts as an anti-freezing agent at high altitudes where temperatures are extremely low. It prevents the fuel from freezing,ensuring the smooth operation of the aircraft engine.

(A) Nitric acid $(HNO_3)$ is used in the pickling of stainless steel to remove surface impurities and oxides.
It is also used as a strong oxidizer in rocket propellants,often in combination with fuels like liquid hydrogen or kerosene.

(B) Lead compounds,specifically tetraethyl lead $(Pb(C_2H_5)_4)$,were previously used as antiknock agents in petrol to improve the octane rating and prevent engine knocking.

(A) In thermal power plants,fossil fuels like $Coal$ are primarily used to produce heat,which converts water into steam to drive turbines.
In fuel cells,such as the $H_2-O_2$ fuel cell,$Hydrogen$ gas is used as the fuel,which reacts with oxygen to produce electricity directly.

(A) In thermal power plants,fossil fuels like coal are primarily used to generate heat,which converts water into steam to drive turbines.
In fuel cells,such as the hydrogen-oxygen fuel cell,hydrogen $(H_2)$ is used as the fuel,which reacts with oxygen $(O_2)$ to produce electricity,water,and heat.

(D) The balanced chemical equation for the reaction is: $Fe_2O_3 + 2Al \rightarrow Al_2O_3 + 2Fe$
The enthalpy change of the reaction is calculated as: $\Delta H_{rxn}^{\ominus} = [\Delta H_{f}^{\ominus}(Al_2O_3) + 2\Delta H_{f}^{\ominus}(Fe)] - [\Delta H_{f}^{\ominus}(Fe_2O_3) + 2\Delta H_{f}^{\ominus}(Al)]$
Since $\Delta H_{f}^{\ominus}$ for elements in their standard state is $0$,we have: $\Delta H_{rxn}^{\ominus} = [-1700 + 0] - [-840 + 0] = -860 \ kJ \ mol^{-1}$
The molar mass of the mixture (for $1 \ mol$ of $Fe_2O_3$ and $2 \ mol$ of $Al$) is: $M_{mixture} = (1 \times 160) + (2 \times 27) = 160 + 54 = 214 \ g$
Heat evolved per gram of the mixture is: $\frac{860 \ kJ}{214 \ g} \approx 4.018 \ kJ \ g^{-1}$
Rounding to the nearest integer,we get $4$.