What is the identity of element q if the ion q2- contains 36 electrons? type the correct symbol for the element in the box. for example, br?

- selenium, Se.

Explanations:- When an element gain electrons then it becomes negatively charged means it forms it's anion. Total electrons of the anion are the sum of electrons and the charge of the anion. In our problem, the element is q and it forms ion. The Total electrons for the anion = electrons of q + 2

As per the given info, there are 36 electrons in ion.

So, 36 = electrons of q + 2

electrons of q = 36 - 2

electrons of q = 34

q, the neutral atom has 34 electrons means it's atomic number is 34. If we check out the periodic table then the element with atomic number 34 is Selenium, Se.

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