Complete the following reaction sequence by drawing in the neutral reagents and products where necessary. the product of this reaction has a molecular formula of c7h6o2 and has a 1h nmr spectrum (cdcl3) of ~12.1 (s), 8.1 (m), and 7.6–7.4 (m) ppm. *show covalent bonds in all compounds.

Benzoic acid

Explanation:

In this case we have a Grignard reaction in which we go from a formula of C6H5Br to C7H6O2. In other words, we add 1 carbon to the molecule. The only way to add one carbon to this molecule is using as a reagent. When this compound is used as electrophile a carboxylic acid is produced.

Respect to the NMR info, we have a downfield singlet signal at 12.1 ppm which is characteristic of the acid hydrogens in the carboxylic acids (see figure 1). When a carboxylic group is added to the benzene we will obtain the benzoic acid which fits with the formula and the NMR info given.

i think that the answer is c

it can be observed without changing the identity of the object.

it depends on what substance you're talking about as well as many other factors. in quantum mechanics, the observation of particles affects the observers ability to measure certain properties. for example: you can know the velocity of a particle, but you can't know it's position; or you can know it's position, but not it's velocity. it's like trying to find out where a grain of sand is by throwing other grains of sand at it. once you find out where it is, it's been moved. it's also like trying to find an answer to the question of whether or not a tree falling in a forest makes a sound if nobody is there to hear it. paradoxically, the only way to find out is to be there and hear it.