# chemistry

How much energy is evolved when 2.65 mg of Cl(g) atoms adds electrons to give Cl1-(g) ions.

No clue how to go about solving this problem as it doesn't really relate to any of my examples in my text book or notes. All I can find that related to this problem is electron affinity and E=(K*Q1*Q2)/r where K is a constant. The EA for Cl is -349 kJ/mol. But I just cant find anything else out about this problem. Any help is great as I'm out of ideas.

1. 👍 1
2. 👎 1
3. 👁 680
For the reaction Cl + e ==> Cl^-, you can look up delta Hof of Cl and for Cl^- and delta H rxn = delta H products - delta H reactants, then convert from mol to 2.65 mg. My text gives +121.7 kJ/mol for deltHof Cl and -226 for Cl^-. Of course that's just delta H; but you could do the same for delta Go.

1. 👍 0
2. 👎 0
2. @DrBob222 - I understand up to the part about the conversion of mol to 2.65 mg. I understand that the enthalpy change is 121.3 kJ/mol for Cl(g) and that would be the reactant part of the equation. But whats the deal with working with 2.65mg and the delta Go?

1. 👍 0
2. 👎 0
3. The ionization (is always concerned with the formation of positive ions) of Chlorine is given by the following equation;
Cl --> Cl+ + e- IE = 1251.19 KJ/mol

While the electron affinity (is always concerned with the formation of negative ions) of Chlorine is given by the following equation;
Cl + e- --> Cl- EA = -349 kJ/mol

# moles of Cl = 0.00265 g/35.5 g/mol
= 0.0000746479 mol
Therefore, the energy involved in the reaction is E = EA x nCl
= -0.026 kJ
Exothermic reaction because the energy is released when the atom gains electrons

1. 👍 1
2. 👎 0

## Similar Questions

1. ### Chemistry

1) The letter "p" in the symbol 4p^3 indicates the ___. A) spin of an electron B) orbital shape*** C) principal energy level D) speed of an electron 2) If the spin of one electron in an orbital is clockwise, what is the spin of

2. ### chem

There are eight markers in a full set, but Flora and Frank each only have seven markers.Flora is missing the red marker, and Frank is missing the blue marker.What can they do so that each has a full set of markers? * steal the

3. ### Chemistry

1) How does the atomic radius change from left to right across a period in the periodic table? A) It tends to decrease*** B)It tends to increase C) It first increases, then decreases D) It first decreases, then increases 2) What

4. ### chemistry

Select all true statements from the following: a. ) Metals are good conductors of heat and electricity. b. ) Nonmetals generally react by forming covalent bonds (i.e. sharing electrons) or by gaining electrons to form anions. c. )

1. ### Science--HELP!!

Can you please check my answers: 1. Dalton's idea that atoms cannot be divided into smaller parts was disproved by the discovery of _________ (electrons?) 2. The description of the structure of the atom is called ______ (atomic

2. ### Chemistry

How many valence electrons does molybdenum have? (give only 1 answer) Go to this site and look for the electrons available in the outside shells. Click on element #42 and scroll down the menu on the left side until you come to

3. ### Chemistry

An electron jumps from energy level 1 to energy level 2 by absorbing a photon of energy 8 eV. What is the most likely energy of the photon that will be emitted by the electron when it moves back down to energy level 1? 2 ev 4 ev 8

4. ### Biology HELP!

1. Which of the following correctly identifies the composition of an oxygen atom? (1 point) 8 protons, 8 electrons, and 8 neutrons 6 protons, 6 electrons, and 6 neutrons 8 protons, 6 electrons, and 7 neutrons 6 protons, 6

1. ### biology

Sulfur has six electrons in its outer most energy level. In ionic bonding, it would tend to ­­­­­­­­­_____________________________. A. take on two more electrons B. give away two electrons C. give away six electrons D.

2. ### chemistry

Which statement correctly describes a covalent bond? The atoms' valence electrons combine to form a network of bonds. Valence electrons are transferred from one atom to the other. The atoms' valence electrons are shared between

3. ### Chemistry - Lewis Dots

Draw the molecule by placing atoms on the grid and connecting them with bonds. Do not identify the charge on each of these species. Include all lone pairs of electrons. H3COCH3 Draw the ion by placing atoms on the grid and

4. ### Science

Metal atoms tend to give away valence electrons when they bond with nonmetal atoms. What type of bond will form between the metal and nonmetal atoms and why does this bond form? 1. A covalent bond will form because electrons are