Answer: Option (6) is the correct answer.
Explanation:
Lattice energy is described as the energy released when formation of 1 mole of an ionic compound occurs due to the combination of its constituent ions.
Also, lattice energy is inversely proportional to the distance between the cation and anion. And, when we move down a group then there occurs an increase in the atomic radii of the atoms.
This means that smaller is the ionic distance between the cation and anion, more will be the lattice energy between the atoms.
Therefore, order from weakest to strongest lattice energy (most positive to most negative) for the given compounds is as follows.
barium chloride < strontium chloride < calcium chloride < magnesium chloride
I think the answer is (4) different molecular structures and different properties. Both structure are crystal. The structure of graphite is organized in layers. And structure of diamond is a strong network of atoms. Also due to the different structures, they have different properties.
<u>Given:</u>
Initial volume of He, V1 = 19.2 L
Initial mass of He, m1 = 0.0860 g
Mass of He removed = 0.205 g
<u>To determine:</u>
The new volume of He i.e V2
<u>Explanation:</u>
Based on Avogadro's law:
Volume of a gas is directly proportional to the # moles of the gas
Volume (V) α moles (n) -----(1)
Atomic mass of He = 4 g/mol
Initial moles of He, n1 = 0.860 g/4 g.mol-1 = 0.215 moles
Final moles of He, n2 = (0.860-0.205)g/4 g.mol-1 = 0.164 moles
Based on eq(1) we have:
V1/V2 = n1/n2
V2 = V1 n2/n1 = 19.2 L * 0.164 moles/0,215 moles = 14.6 L
Ans: New volume is 14.6 L
Ionic salt dissociate completely in water particularly in water at low concentration.
The molal freezing point of depression constant for water is 1.85kg/k/mol
therefore depression of freezing point =1.853 x 0.100 x 2.32=0.429 degrees celsius
hence solute freeze at - 0.429 degree celsius
