Which of the following statements is correct about reversible reactions in closed systems?

a. initially, the concentration of reactants is low, so the reaction rate of the forward reaction is also low. over time, the rates of the forward and reverse reactions equalize, and the system reaches a state of chemical equilibrium.

b. initially, the concentration of reactants is low, so the reaction rate of the forward reaction is also low. over time, the rate of the forward reaction becomes zero, and the system reaches a state of chemical equilibrium.

c. initially, the concentration of products is low, so the reaction rate of the reverse reaction is also low. over time, the rate of the forward reaction becomes zero, and the system reaches a state of chemical equilibrium.

d. initially, the concentration of products is low, so the reaction rate of the reverse reaction is also low. over time, the rates of the forward and reverse reactions equalize, and the system reaches a state of chemical equilibrium.

the answer is d

because the reverse reaction is slow

answer: - 3.) the oxidation state of nitrogen in no changes from +2 to 0, and the oxidation state of carbon in co changes from +2 to +4 as the reaction proceeds.

solution: - as per the rules, oxidation number of oxygen in its compounds is -2. the sum of oxidation numbers of all the elements of a molecule or compound is zero.

also, the oxidation number in elemental form is zero.

in no, the oxidation number of o is -2 so the oxidation number of n is +2 so that the sum is zero.

similarly, the oxidation number of c in co is +2 and o is -2.

on product side the oxidation number of n is 0 as it is in the elemental form() .

oxidation number of c in carbon dioxide is +4 as there are two oxygen in it and we know that each oxygen is -2.

so, oxidation number of n is changing from +2 to 0 and the oxidation number of c is changing from +2 to +4.

since nitrogen is reduced and hence no is acting as an oxidizing agent. carbon is oxidized and so co is acting as a reducing agent.

so, the right choice is number 3.)the oxidation state of nitrogen in no changes from +2 to 0, and the oxidation state of carbon in co changes from +2 to +4 as the reaction proceeds.

they are made of gases.

they have a spherical shape.

they make energy through fusion.