3. if the dartboard below is used to model an atom, which subatomic particles would be located at z?

Answer : The protons and neutrons subatomic particles will be located at Z.

Explanation :

In the model of an atom, there are three subatomic particles. Protons, neutrons and electrons are the subatomic particles.

The protons and the neutrons subatomic particles are located inside the nucleus and the electrons subatomic particle are located around or outside the nucleus.

The protons are positively charged, electrons are negatively charged and neutrons are neutral that means it has no charge.

In the given dartboard, Z is the nucleus in which the protons and neutrons subatomic particles are present and x, w & y are the electrons because they are located around the nucleus.

Hence, the protons and neutrons subatomic particles will be located at Z.

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