Define a salt bridge. define a salt bridge. a pathway between the cathode and anode in which ions are oxidized. a pathway, composed of salt water, that ions pass through. a pathway between the cathode and anode in which ions are reduced. a pathway by which counterions can flow between the half-cells without the solutions in the half-cell totally mixing. a pathway in which no ions flow.

A pathway by which counter ions can flow between the half-cells without the solutions in the half-cell totally mixing.

Explanation:

Salt bridge is a link between oxidation half and reduction half of a galvanic cell.

Functions of salt bridge are:

Maintaining electrical neutrality

Preventing cell from reaching equilibrium

For creating salt bridge, a U shaped glass tube is filled with an inert electrolyte. Electrolytes used in the salt bridge generally do not reacts with the cell chemicals.

Cations and anions of the electrolytes have same ionic conductivity and hence, migrate with the same speed.

Most commonly potassium chloride, sodium chloride and potassium nitrate are used as an electrolyte in salt bridge.

Electrolyte are generally mixed with agar agar to prevent mixing of chemicals in the two half cells.

< > according to newton's third law of motion, forces always act in equal but opposite pairs. another way of saying this is for every action, there is an equal but opposite reaction.< >

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