Name: Kareem Daniels Due: September 8, 2015Prelab #3 : A practical study of some group II elements

Prelab (10pts)

Table 3.6 Fill in the following table concerning general properties of Group II elements. You will need to include a copy in your lab.. You can get most of the information from http://www.chemicool.com/; however, there is an error for the values of electron affinity and ionization energies for magnesium, so you will need to get those values for this element from another source

Element Be Mg Ca Sr BaAtomic number 4 12 20 38 56Electronic configuration 1s2 2s2 1s2 2s2 2p6 3s2 1s2 2s2 2p6 3s2 3

p6 4s2 [Kr] 5s2 [Xe] 6s2

Atomic radius (nm)

0.112 0.15 0.18 0.215 0.215

Ionic radius (nm) 0.045 0.086 0.114 0.132 0.149Electron affinity 0 kJ mol-1 0 kJ mol-1 2 kJ mol-1 5 kJ mol-1 14 kJ mol-1

electronegativity 1.57 1.31 1 0.95 0.89First ionization energy

899.5 kJ mol-1 737.7 kJ mol-1 589.8 kJ mol-1 549.5 kJ mol-1 502.9 kJ mol-1

Second ionization

1757.1 kJ mol-1 1450.6 kJ mol-1 1145.4 kJ mol-1 1064.2 kJ mol-1 965.2 kJ mol-1

Standard electrode potential

-1.847 -2.363 -2.866 -2.888 -2.906

Answer the following questions in brief

1. What gas do you expect to be evolved in experiment 1? How can you test for it?(1pt)Hydrogen gas is expected to be evolved in experiment 1. This can be tested by using a lighted splint.

2. How can you test for production of HCl gas in experiment 3? (1pt)Hydrogen chloride gas turns moist litmus paper from blue to red and moist universal indicator paper to red. Hydrogen chloride gas will put out a lit splint.

3. What is lime water? What is it testing for in experiment 4? (1pt)Lime water is a solution of calcium hydroxide in water. In experiment 4, the lime water is testing the thermal stability of the metal carbonates i.e. the ease of which the carbonates of the metals are decomposed.

4. Look up the general solubility rules of group II metal compounds. Using this information, predict which mixtures of cations and anions would be insoluble. Place your information in the table below.(2pts)

Solubility of some compounds of group II elements

Cation/Anion Hydroxide Sulphate CarbonateMg2+

Insoluble Soluble Insoluble

Ca2+Soluble Insoluble Insoluble

Ba2+Soluble Insoluble Insoluble

References

Chemed.chem.purdue.edu,. (2015). Ionization Energy and Electron Affinity. Retrieved 7 September 2015,

from http://chemed.chem.purdue.edu/genchem/topicreview/bp/ch7/ie_ea.html#first

Chemicool.com,. (2015). Periodic Table of Elements and Chemistry. Retrieved 7 September 2015, from

http://www.chemicool.com/

Chemwiki.wikidot.com,. (2015). Standard Electrode Potentials - Chemwiki. Retrieved 7 September 2015,

from http://chemwiki.wikidot.com/standard-electrode-potentials#toc2

Clark, J. (2015). Reactions of the Group 2 elements with water. Chemguide.co.uk. Retrieved 7 September

2015, from http://www.chemguide.co.uk/inorganic/group2/reacth2o.html

Clark, J. (2015). Solubility of the hydroxides, sulphates and carbonates of the Group 2 elements in

water. Chemguide.co.uk. Retrieved 7 September 2015, from

http://www.chemguide.co.uk/inorganic/group2/solubility.html

Gcsescience.com,. (2015). GCSE CHEMISTRY - What is the Test for Hydrogen Chloride Gas? - How do I

test for Hydrogen Chloride Gas? - How is Hydrogen Chloride Gas Collected? - GCSE SCIENCE..

Retrieved 7 September 2015, from http://www.gcsescience.com/itesthydrogenchloride.htm

Nuffieldfoundation.org,. (2015). Thermal decomposition of metal carbonates | Nuffield Foundation. Retrieved

7 September 2015, from http://www.nuffieldfoundation.org/practical-chemistry/thermal-decomposition-

metal-carbonates

Periodictable.com,. (2015). Electron Affinity for all the elements in the Periodic Table. Retrieved 7 September

2015, from http://periodictable.com/Properties/A/ElectronAffinity.v.html