Answer:-A. It is less than 890 kJ/mol because the amount of energy required to break bonds is less than the amount of energy released in forming bonds.
Explanation: Endothermic reactions are defined as the reactions in which energy of the product is greater than the energy of the reactants. The total energy is absorbed in the form of heat and 
for the reaction comes out to be positive.
Exothermic reactions are defined as the reactions in which energy of the product is lesser than the energy of the reactants. The total energy is released in the form of heat and for the reaction comes out to be negative.
In the formation of new bonds more energy is released than is required to break the existing bonds, heat is released.
In the formation of bonds less energy is released than is required to break the existing bonds, heat is absorbed.
1) Reaction
<span>NH4Cl(s) ---> NH3(g) + HCl(g)
2) equilibrium equation, Kc
Kc = [NH3] * [HCl]
3) Table of equilibrium formation
step concentrations
</span>
<span> NH4Cl(s) NH3(g) HCl(g)
start 1.000 mole 0 0
react - x
produce +x + x
------------------ ---------- -----------
end 1 - x +x +x
1 - x = 0.3 => x = 1 - 0.3 = 0.7
[NH3] = [HCl] = 0.7/0.5 liter = 1.4 (I used 0.500 dm^3 = 0.5 liter)
4) Equilibrium equation:
Kc = [NH3] [HCl] = (1.4)^2 = 1.96
Which is the number that you were looking for.
Answer: Kc = 1.96
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Melting point is dependent on the intermolecular forces which means the bonds between the molecules of bromine as it is a simple molecular structure the intermolecular bonds of bromine are weak bcz they are weak vandervaal forces thats why Bromines melting point is low..In short when intermolecular bomds are weak the M.P is lower
Answer:
6.25 grams is the mass of solute dissolved.
Explanation:
w/w % : The percentage mass or fraction of mass of the of solute present in total mass of the solution.
Mass of the solution = 50.0 g
Mass of the solvent = x
w/w % = 12.5%
x = 6.25 g
6.25 grams is the mass of solute dissolved.
The ideal gas law is P1V1/T1 = P2V2/T2. STP means the temperature is 273 K and pressure is 101.3 kPa. According to this formula, the new volume V2=2.15*58*273/(298*101.3) = 1.13 L.
