<u>Given:</u>
H2(g) + Cl2 (g) → 2HCl (g)
<u>To determine:</u>
The enthalpy of the reaction and whether it is endo or exothermic
<u>Explanation:</u>
Enthalpy of a reaction is given by the difference between the enthalpy of formation of reactants and products
ΔH = ∑nHf (products) - ∑nHf (reactants)
= [2Hf(HCl)] - [Hf(H2) + Hf(Cl2)] = 2 (-92.3) kJ = - 184.6 kJ
Since the reaction enthalpy is negative, the reaction is exothermic
<u>Ans:</u> The enthalpy of reaction is -184. kJ and the reaction is exothermic
C. Cello playing music at a concert
Explanation:
use the term electron sheilding, the more electrons between the valence el3ctron and nucleus the easier to lose the valence electron (more sheilding = easier to lose)
Explanation:
When water is frozen then it is known as ice and its state is solid. So, its molecules will be held closer to each other as they are held by strong intermolecular forces of attraction.
As a result, its temperature will be minimum as its molecules have least kinetic energy.
It is known that kinetic energy of a substance is directly proportional to temperature.
As, K.E = 
where K.E = kinetic energy
T = temperature
k = boltzmann constant
When solid changes into liquid state then it means molecules of a substance has gained kinetic energy due to which there occurs more collisions between the molecules.
Hence, temperature of substance also increases.
Whereas when liquid state of a substance changes intro vapor state then it means that more kinetic energy has gained by the molecules due to which there will be much more collisions between the molecules.
Hence, temperature will be maximum in vapor state.
Answer:
THE VOLUME OF THE BALLOON IS 1.45 L
Explanation:
At sea level:
Volume = 2 L
Pressure = 1 atm
Temperature = 12 °C
At 30000 ft altitude:
Pressure = 0.30 atm
Temperature = -55°C
Volume = unknown
Using the general gas formula:
P1 V1 / T1 = P2 V2 / T2
Re-arranging the formula by making V2 the subject of the equation, we have;
V2 = P1 V1 T2 / T1 P2
V2 = 1 * 2 * 12 / 0.30 * 55
V2 = 24 / 16.5
V2 = 1.45 L
The volume of the balloon at the temperature of -55 C and 0.30 atm is 1.45 L
