Select the ion.
hcl
h2o
h3o+1

Answer : The correct option is,

Explanation :

Ion : It is formed by the loss or gain of one or more electrons. It is an electrically charged atom or group of atoms.

Positive charged ion is formed by the loss of electrons and is known as cation and negative charged ion is formed by the gain of electrons and known as anion.

From the given options,

and are the neutral molecules. while the is a positive ion species that is cation because it has (+1) charge.

Hence, the correct option is,

2b2t

explanation:

2b2t

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