A carbocation is an example of a(an) . Does a carbocation accept a pair of electrons, or does it donate a pair of electrons? A. Electrophile. The carbocation accepts a pair of electrons.
B. Nucleophile. The carbocation accepts a pair of electrons.
C. Electrophile. The carbocation donates a pair of electrons.
D. Nucleophile. The carbocation donates a pair of electrons.

Option A. The carbocation accepts a pair of electrons.

Explanation:

A carbocation is defined as a positively charged carbon, which is bound to 3 substituents. Since it has no electrons  nonbonding, it only has six electrons in its valence shell. With only six electrons in its valence shell, a carbocation is a powerful electrophile (and Lewis acid) and can react with any nucleophile that is found.

Carbocations are proposed as intermediates in many  organic reactions. They also work like free radicals, which are electron-deficient species.

Same as free radicals, the carbocations are stabilized by alkyl substituents.

answer : third trial had the contaminated sample and the correct value for dhrxn should be 1000 kj/mol

explanation :

let us write down the given equations

equation 1 :

equation 2 :

equation 3 :

let us use hess's law to find out which 2 equations can be added to get the third equation.

let us reverse equation 2 and multiply it by 2. the new equation that we get is,

equation 4 :

let us add equation 1 & 4

the above equation is similar to equation 3 but has different value for dhrxn.

therefore third trial had the contaminated sample and the correct value for dhrxn should be 1000 kj/mol