Since this process involves a matter-state change from solid to liquid, melting is occurring.
Ionic compounds have very strong intermolecular 'bonds': this is because it is formed by a metal atom donating one or more electrons to a non-metal atom in order to result in complete valence shells, with the effect that opposite ions are formed (opposites attract). Hence a large input of energy is needed to overcome these 'bonds' and form a liquid from the giant solid ionic lattice - therefore ionic compounds have high melting and boiling points.
Conversely a covalent bond occurs between two non-metal atoms - unlike ionic compounds which form giant ionic structures, covalent bonds are used to form molecules. These only have weak intermolecular forces, which need a small energy input to overcome: therefore the melting and boiling points will be much lower.
Considering that the compound has been taken from the freezer, which is 0 degrees celcius or lower, the state change has occurred at a low temperature. This makes it extremely likely that the compound is covalent.
In conclusion, the correct answer is d.
Answer:
C. 2.
Explanation:
The total reaction order of this reaction is second order (2). For a second order reaction ,the rate depends on two variable concentration terms which may or may not be same.
Given that:
Two reactants combine to form a product in the reaction A + B → C
The above reaction is bimolecular as two molecules are involved in the reaction.
If and are the concentrations of A and B respectively at any time t, then assuming that the reaction is of first order with respect to both A and B , the overall order is second and the reaction rate is given by:
where;
= specific rate constant for a second order reaction and becomes the rate of the reaction when both and are unity.
Answer:
nine
There are nine orbitals in the n = 3 shell. There is one orbital in the 3s subshell and three orbitals in the 3p subshell. The n = 3 shell, however, also includes 3d orbitals. The five different orientations of orbitals in the 3d subshell are shown in the figure below.
Explanation:
Answer: The correct statements about thermal conductivity are:
- The thermal conductivity of metals is generally higher than that of liquids.
- The thermal conductivity of solids is generally higher than that of liquids.
Explanation:
The rate at which transfer of heat takes place from one object to another by conduction over a unit cross section area of a material is called thermal conductivity.
Hence, more is the distance between atoms of a substance less will be its thermal conductivity. This is because more is the space between molecules of a substance more will be their random motion due to which there will be less effective energy transport.
The thermal conductivity of metals is very high than liquids.
Also, the thermal conductivity of solids is generally higher than that of liquids.
As gases have more space between its molecules so they have less thermal conductivity.
Thus, we can conclude that the correct statements about thermal conductivity are:
- The thermal conductivity of metals is generally higher than that of liquids.
- The thermal conductivity of solids is generally higher than that of liquids.