Answer: b. 
is positive and 
is positive.
Explanation:-
As the temperature of the pack drops, the energy has been absorbed from the pack for dissolution of 
in water. Thus as the energy has been absorbed in the reaction, the reaction is endothermic and the change in enthalpy i.e. is positive.
The entropy is the measure of degree of randomness. The entropy increases when the randomness increases and the entropy decreases when the randomness decreases. When a substance dissolves in water, it dissociate into ions and hence the randomness increases thus the change in entropy i.e. is positive.
Answer:
The structures are shown in the figure.
Explanation:
The primary hydrogens are those which are attached to primary carbon.
Primary carbons are the carbons which are attached to only one carbon.
Primary carbons is bonded to three hydrogens.
In order to draw such structure we will draw structures which will have carbon with three hydrogens or no hydrogens (quaternary)
The structures are shown in the figure with clear marking.
Answer: Answer:
"The arrangement of atoms or ions in a crystal " is described by the terms body-centered cubic and face-centered cubic.
Explanation:
Face centred cubic system explains the crystal structure where an atom is present at each cubic corner of the crystal and the centre of each cube face. Meaningfully, a closed packed plane where at each "face of the cube" atoms touch the alongside face diagonals.
Whereas in body centric cube system has the lattice point present at the 8 corners of cell and an additional one at the center of the cell. Thus, both explains how the atom or ions are placed or arranged in a crystal.
Explanation: Hope this helps :)
A synthesis would be A+B-->AB its combining, decomposition is AB-->A+B, its the breaking up of a substance.
In order to get HgO you would need 2Hg+1O2=2HgO. Since oxygen is diatomic you need two when it stands alone causing you to need two mercuries to balance out the reactants and the product I hope this helps
