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Measuring delta U and delta H using calorimetry

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Value of Delta U by calorimetry - definition

The calorimeter is isolated from the rest of the universe, we can define the reactants to be the system and the rest of the calorimeter (bomb and water) to be the surroundings.The change in internal energy of the reactants upon combustion can be calculated : $d U_{s y s} = - n C_{v} d T$

Measurement of Delta H by calorimetry - definition

We can calculate change in enthalpy by the following formula:

Δ H = Δ U + R T Δ n_{g a s}

Principle of calorimetry - law

The principle of calorimetry (or principle of mixtures) states that for an insulated system, heat energy lost by the hot body is equal to the heat energy gained by the cold body.

m_{1} c_{1} (t_{1} - t) = m_{2} c_{2} (t - t_{2})

Note: Heat transfer occurs until both the bodies attain the same temperature(

t

Mayuri was performing thermometric titration and she took 100 ml of 1 M sulphuric acid and started adding 1 M calcium hydroxide and she plotted a graph of temperature vs volume of the titrant added. In that experiment she found that temperature was initially increasing and then it started decreasing. The maximum of the graph is obtained at 100 ml. calcium hydroxide. What will be the enthalpy change of this reaction. (Given $Δ H$ =-13.7 kcal for equivalent)

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Consider the following reactions. In which case the formation of product is favoured by decrease in pressure?
(1) $C O_{2} (g) + C (s) \to 2 C O (g)$ ; $Δ H = + 172.5$ kJ
(2) $N_{2} (g) + 3 H_{2} (g) \to 2 N H_{3} (g)$ ; $Δ H = - 91.8$ kJ
(3) $N_{2} (g) + O_{2} (g) \to 2 N O (g)$ ; $Δ H = + 181$ kJ
(4) $2 H_{2} O (g) \to 2 H_{2} (g) + O_{2} (g); Δ H = 484.6$ kJ

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Statement I: In adsorption process, the value of $Δ H$ is always negative.
Statement II: During adsorption surface area of adsorbent decreases.
Which of the above statement is/are true? Choose the correct option.

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The standard heat of combustion of propane is $- 2220.1 k J / m o l$ . The standard heat of vaporization of liquid water is $44 k J / m o l$ . What is the $△ H^{o}$ of the reaction :
$C_{3} H_{8} (g) + 5 O_{2} (g) \to 3 C O_{2} (g) + 4 H_{2} O (g)$ ?

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$N X$ is produced by the following step of reactions:

$M + X_{2} ⟶ M X_{2}$

$3 M X_{2} + X_{2} ⟶ M_{3} X_{8}$

$M_{3} X_{8} + N_{2} C O_{3} ⟶ N X + C O_{2} + M_{3} O_{4}$

How much $M$ (metal) is consumed to produce $206 g m$ of $N X$ ?
(Take atomic weight of $M = 56, N = 23, X = 80$ )

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A bomb calorimeter is used to measure the value of heat of reaction at a constant

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constant pressure.
The thermal capacity of calorimeter system is $17.7 k J$ $K^{- 1}$ . ( $R = 8.313 m o l^{- 1} K^{- 1}$ ) (only magnitude in nearest integer in kj/mol)

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The quantity of heat required to raise the temperature of 2000 g of water from 10 $^{o}$ C to 50 $^{o}$ C is

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The heat capacity of a bomb calorimeter is $300 J / K$ . When $0.16 g m$ of methane was burnt in this calorimeter the temperature rose by $3^{\circ} C$ . The value of $△ U$ per mole will be

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If melting one mole of ice to water requires $6$ kJ of enthalpy, then freezing of water to two mole of ice will require ________ kJ of energy.

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Value of Delta U by calorimetry - definition

Measurement of Delta H by calorimetry - definition

Principle of calorimetry - law

Related questions

Consider the following reactions. In which case the formation of product is favoured by decrease in pressure? (1) CO2​(g)+C(s)→2CO(g); ΔH=+172.5 kJ (2) N2​(g)+3H2​(g)→2NH3​(g); ΔH=−91.8 kJ (3) N2​(g)+O2​(g)→2NO(g); ΔH=+181 kJ (4) 2H2​O(g)→2H2​(g)+O2​(g);ΔH=484.6 kJ

Statement I: In adsorption process, the value of ΔH is always negative. Statement II: During adsorption surface area of adsorbent decreases. Which of the above statement is/are true? Choose the correct option.

The standard heat of combustion of propane is −2220.1 kJ/mol. The standard heat of vaporization of liquid water is 44 kJ/mol. What is the △Ho of the reaction : C3​H8​(g)+5O2​(g)→3CO2​(g)+4H2​O(g)?

NX is produced by the following step of reactions: M+X2​⟶MX2​ 3MX2​+X2​⟶M3​X8​ M3​X8​+N2​CO3​⟶NX+CO2​+M3​O4​ How much M (metal) is consumed to produce 206gm of NX?(Take atomic weight of M=56,N=23,X=80)

A bomb calorimeter is used to measure the value of heat of reaction at a constant

constant pressure. The thermal capacity of calorimeter system is 17.7kJ K−1. (R=8.313mol−1K−1) (only magnitude in nearest integer in kj/mol)

The quantity of heat required to raise the temperature of 2000 g of water from 10oC to 50oC is

The heat capacity of a bomb calorimeter is 300 J/K. When 0.16 gm of methane was burnt in this calorimeter the temperature rose by 3∘C. The value of △U per mole will be

If melting one mole of ice to water requires 6 kJ of enthalpy, then freezing of water to two mole of ice will require ________ kJ of energy.

Statement I: In adsorption process, the value of $Δ H$ is always negative.
Statement II: During adsorption surface area of adsorbent decreases.
Which of the above statement is/are true? Choose the correct option.

The standard heat of combustion of propane is $- 2220.1 k J / m o l$ . The standard heat of vaporization of liquid water is $44 k J / m o l$ . What is the $△ H^{o}$ of the reaction :
$C_{3} H_{8} (g) + 5 O_{2} (g) \to 3 C O_{2} (g) + 4 H_{2} O (g)$ ?

$N X$ is produced by the following step of reactions:

$M + X_{2} ⟶ M X_{2}$

$3 M X_{2} + X_{2} ⟶ M_{3} X_{8}$

$M_{3} X_{8} + N_{2} C O_{3} ⟶ N X + C O_{2} + M_{3} O_{4}$

How much $M$ (metal) is consumed to produce $206 g m$ of $N X$ ?
(Take atomic weight of $M = 56, N = 23, X = 80$ )

constant pressure.
The thermal capacity of calorimeter system is $17.7 k J$ $K^{- 1}$ . ( $R = 8.313 m o l^{- 1} K^{- 1}$ ) (only magnitude in nearest integer in kj/mol)

The quantity of heat required to raise the temperature of 2000 g of water from 10 $^{o}$ C to 50 $^{o}$ C is

The heat capacity of a bomb calorimeter is $300 J / K$ . When $0.16 g m$ of methane was burnt in this calorimeter the temperature rose by $3^{\circ} C$ . The value of $△ U$ per mole will be

If melting one mole of ice to water requires $6$ kJ of enthalpy, then freezing of water to two mole of ice will require ________ kJ of energy.