Answer:
Electromeric effect refers to a molecular polarizability effect occurring by an intramolecular electron displacement (sometimes called the 'conjugative mechanism' and, previously, the 'tautomeric mechanism') characterized by the substitution of one electron pair for another within the same atomic octet of electrons.
Explanation:
Physical changes are the changes that does not lead to any change in chemical composition of a substance.
For example, mass, density, volume are all physical changes.
On the other hand, a change that leads to formation of a new compound by changing the chemical composition of reactants or combining atoms is known as a chemical change.
For example, combustion, toxicity, reactivity etc are all chemical changes.
Therefore, given changes are identified as follows.
- Coal burning : It is a combustion reaction. Hence, it is a chemical change.
- Ice melting : Physical state of water changes from solid to liquid. Hence, it is a physical change.
- mixing chocolate syrup with milk : No new compound is forming as there is no chemical reaction occurring. Hence, it is also a physical change.
- explosion of a firecracker : It shows reactivity of fire cracker. Hence, it is a chemical reaction.
- magnetizing of a screwdriver : It shows physical attraction between the magnet and screwdriver. Hence, it is a physical change.
The energy involved in melting in freezing is heat, At 0 degrees Celsius ice is at an equilibrium where the heat energy absorbed during melting (endothermic) and heat energy dispersed during freezing (exothermic). When ice melts its absorbs heat energy to change states, when water freezes to ice it dispersed heat energy so that the particles can move slow enough to be almost frozen, but still very small vibrations throughout the ice. Particles in the frozen state are packed tightly and help together by a crystal lattice and IMF's, liquid is free flowing with free floating particles that can move freely from one another particle.
Answer:
<h2>0.05 moles</h2>
Explanation:
To find the number of moles in a substance given it's number of entities we use the formula
where n is the number of moles
N is the number of entities
L is the Avogadro's constant which is
6.02 × 10²³ entities
From the question we have
We have the final answer as
<h3>0.05 moles</h3>
Hope this helps you
