Answer questions 1-5 based on the chemical behaviors observed in this lab exerci
ID: 857170 • Letter: A
Question
Answer questions 1-5 based on the chemical behaviors observed in this lab exercise and the data presented in the Introduction. 1. Would you expect the freshly exposed surface of a piece of lithium (Li) to react with atmospheric O2 at room temperature? Explain. 2. What would you expect to observe if you placed a piece of Li in a beaker containing water? Explain. 3. What precautions would you take before testing the behavior of rubidium (Rb) in water? Explain? 4. How would you expect the reactivity of cesium (Cs) in water to compare with the behavior of Rb? Explain. 5. How would you expect the behavior of barium (Ba) in water to compare with the behavior of Cs? Explain. 6. Explain the trends in reactivity in terms of other periodic trends, (i.e., atomic size, ionization energy, etc.).Explanation / Answer
a) Lithium react atmospheric oxygen to lithium oxide
4Li + O2 ----------> 2Li2O
b) Lithium metals reacts slowly with water to form a colourless solution of lithium hydroxide (LiOH) and hydrogen gas (H2). The resulting solution is basic because of the dissolved hydroxide.
c) handle under inert atmosphere. wear protective gloves, protective cloth, eye protection and face protection.
d) cesium is more reactive when compare to rubidium. as we go down the group reactivity will increase.
e) cesium is more reactive when compare to barium.
f) atomic size will increase as we go down the group therefore the reactivity will increase due more sheilding
ionization energy will decrease as we go down the group therefore the reactivity will increase
electronegativity will decrease as we go the group therefore the reactivity will increase.