Answer:- 
Explanations:- Lattice energy depends on two factors, charge and size.
High charge and small size gives higher lattice energy where as low charge and bigger size gives lower lattice energy.
in LiCl, NaCl and KCl, the anion is same and also the charges for Li, Na and K are also same. The deciding factor here is the size of cations. Since the size increases as we move down a group, the order of size of these three atoms is Li<Na<K.
The order of lattice energy is exactly opposite as it's increases as the size decreases.
Now, if we look at magnesium chloride and strontium chloride then again the anion is common but the metals have higher charge as compared to the alkali metals(Li, Na and K). So, lattice energy values must be higher for these two compounds. If we compare Mg and Sr then size of Mg is smaller and so the lattice energy would be greater for this.
Hence, the increasing order of lattice energy is .
Answer:
The correct answer is option C
Explanation:
According to Heisenberg's principle "At the instant of time when the position is determined, that is, at the instant when the photon is scattered by the electron, the electron undergoes a discontinuous change in momentum. This change is the greater the smaller the wavelength of the light employed, i.e., the more exact the determination of the position. At the instant at which the position of the electron is known, its momentum therefore can be known only up to magnitudes which correspond to that discontinuous change; thus, the more precisely the position is determined, the less precisely the momentum is known".
Hence, this principle made scientists to realize that electrons could not be located in defined orbits which a contradictory of Bohr's model.
Answer: Metals are malleable. Most metallic elements are solids at room temperature.
Explanation:
The balanced chemical equation for the combustion of butane is:
Δ
= Σ
Δ
-Σ
Δ
= ![[{8*(-393.5kJ/mol)}+{10*(-241.82kJ/mol)}]-[{2*(-125.6kJ/mol)}+13*(0 kJ/mol)}]](https://tex.z-dn.net/?f=%5B%7B8%2A%28-393.5kJ%2Fmol%29%7D%2B%7B10%2A%28-241.82kJ%2Fmol%29%7D%5D-%5B%7B2%2A%28-125.6kJ%2Fmol%29%7D%2B13%2A%280%20kJ%2Fmol%29%7D%5D)
=[-3148kJ/mol+(-2418.2kJ/mol)]-[(-251.2kJ/mol)+0]
= -5315 kJ/mol
Calculating the enthalpy of combustion per mole of butane:
Therefore the heat of combustion per one mole butane is -2657.5 kJ/mol
Correct answer: -2657.5 kJ/mol
