A discharging lead-acid battery is best described as 1.) chemical cells that use an electrical current

2.) chemical cells that produce an electrical current

3.)electrolytic cells that use an electric current

4.)electrolytic cells that produce an electric current

The correct option is;

2.) Chemical cells that produce an electric current

Explanation:

A discharging lead-acid battery is an electrochemical cell that produces electrical energy through the chemical reaction taking place at the battery electrodes which have lead as the anode and lead oxide as the cathode which result in the flow of an electric current, thereby converting chemical energy of the lead, lead oxide and aqueous sulfuric acid system into electrical energy, therefore, it is a chemical cell that produces an electric current.

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