Correct Answer: option 4: <span>E and D show that the energy of the products is less than that of the reactants.
Reason: For the reaction: Q + R </span>→ N + M <span> (reactant) (product)
From the graph, it is clearly evitable that E represent energy of reactant, while D represents energy of products. Also, value of D is less as compared to E. This signifies that, products (N+M) has less energy as compared to reactants (Q+R). Also, the reaction is exothermic in nature. </span>
<span>Answer: the fourth option: E and D show that the energy of the products is less than that of the reactants.
Explanation: </span><span />
<span>The graph shows how the energy of the species (vertical axis) changes as the reaction progress (horizontal axis). </span><span />
<span>We can see each option: </span><span />
<span>1) A and C show that the reaction enthalpy is less than the activation energy. </span><span />
<span>FALSE: C is the energy difference between products and reactants, and that is the enthalpy of the reaction, while C is the activation energy (the peak of the curve).
2) G and E show that this reaction is an endothermic process with heat release. </span><span />
<span>FALSE: since G is below E, the final energy is less than the initial energy, meaning that the reaction released energy and, consequently, the reaction is exhotermic.
3) B and F show that the activated complex has less energy than the reactants. </span><span /> FALSE <span>The activated complex is at the peak of the curve, so it hass more energy than the reactants. </span><span />
<span>4) E and D show that the energy of the products is less than that of the reactants.
</span><span>TRUE: indeed D is below E meaning the the energy of the products (D) is less than the energy of the reactants (E).</span>
81. There is 1 carbon, 2 chlorine and fluorine atoms in Freon 12. To draw them it forms a cross with C in the middle and Cl and F both on the opposite side. Cl l F - C- F l Cl
82. Freon-12 and Freon-14 are called halocarbons or just halides.
Covalent compounds are compounds that are formed as a result of covalent bonding between nonmetal atoms.
Covalent compounds occur only between non metals, where atoms of the nonmetals involved join to form a covalent bond as a result of sharing of electrons.
<u><em>Electrons shared during the formation of covalent bond, may be from one atom involved or each atom contributing equally to the bond formation.</em></u>
An example of covalent compounds include, phosphorus (v) oxide, methane, water, CO2,etc.