In a chemical reaction occurring in an open beaker, the reactants have a mass of 10.0 g and contain 1000 j of energy. the products in the beaker contain a mass of 5.0 g and 500 j of energy. which best explains the difference in energy and mass as reactants are converted to products?

Explanation:

This happens because the beaker is open.

The Law of Mass Conservation says that in a close system all the mass and energy should be the same.

If the system is open, as in the case, we can have loss of mass, due to formation of gas, that will leave the beaker to the environment, and we can also have loss of energy, because the system will exchange the energy, as heat, with the environment, causing a loss on the total energy.

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.

i believe it is c.) 1575 j.