Which reaction is exothermic?
ch4 + 2o2 --> co2 + 2h2o + 891 kj
nh4no3 + h2o + 25 kj --> nh4+(aq) + no3-(aq)
2h2o + 286 kj --> 2h2 + o2
n2 + o2 + 181 kj--> 2no

Correct option is

Explanation: Exothermic reactions are the reactions in which energy is released to the surroundings.

For these reactions, the energy term should be present on the product side and in the options given the energy term is present in the reaction,

All other reactions have energy term on the reactant side and hence, they are considered as endothermic reactions.

Ans: a) CH4 + 2O2 -->CO2 + 2H2O + 891 kJ

Chemical reactions can be broadly classified as: Exothermic and endothermic reactions.

Exothermic reactions proceed with the release of heat. Here the potential energy of the reactants is greater than that of the products and the reaction enthalpy is negative.

In contrast, Endothermic reactions proceed with the absorption of heat. Here the potential energy of the reactants is lower than that of the products and the reaction enthalpy is positive.

In the given examples only

CH4 + 2O2 -->CO2 + 2H2O + 891 kJ

is an exothermic reaction as it involves production or release of 891 kJ of heat.

The other reactions are endothermic since they involve absorption of heat.

when—without warning—something provokes your anger, you may struggle not to succumb to it. since what typically makes you mad is feeling powerless in the face of what seems unfair, your anger is mostly an attempt at a “quick fix” to right the balance. it’s as though you’re raising a fist in protest, proclaiming that you’re not going to capitulate to such injustice.

there are, however, a multitude of problems related to this immediate, push-back reaction of anger. and probably the key one is that almost never does it resolve the issue that gave rise to it. such reactive anger is probably best understood as self-defeating. as david burns, the author of the seminal self- book feeling good, observes: if realistically, acting on your anger is to make any sense, it needs to meet two criteria—which, in almost every case, is frankly impossible. that is, your anger must:

be directed toward a person who has intentionally (and needlessly) behaved in a hurtful way toward you; and

be beneficial or advantageous to you (i.e., assist you in achieving a desired goal).

i think you’ll agree that only rarely can you claim that your anger is both warranted and , whether to yourself or the relationship.

so let me offer you a two-step alternative to abandoning your better judgment and giving in to the temptation of anger—one that should neutralize your anger in seconds. or, when you’re really angry, in minutes.

but keep in mind that you must really want to execute these steps, be sufficiently motivated to perform them. which means overcoming more unconscious resistance than you might ever have imagined. because there are many immediate “advantages” of anger that can interfere with your resolve, i’ll suggest a few of them that might interfere with your employing this powerful method to rid yourself of counter-productive anger.

explanation:

1 a

2 d

3 a

4 c

explanation: