rubidium is the fourth element in group 1. predict the following properties of rubidium and its compunds:
A. appearence
B. hardness
C. reaction with water
D. appearance and solubility of rubidium chloride
E. electrical conductivity
Look at the properties of the other elements that you know in group 1. Rb should be similar. For example, D. I now NaCl is a white crystalline solid that is soluble in water. I would expect RbCl to be the same.
if i am wrong correct me- it is very hard to cut
its reaction with water is vigorous
its appearance-stored in oil white solid lump
The reaction with water is vigorous.
The appearance stored in oil should be a silvery solid
but the first one is not correct. Sodium is a soft silvery metal. I would expect Rb to be a soft silvery metal also. It is easily cut into small pieces with a pocket knife.
To predict the properties of rubidium (Rb) and its compounds, we can look at the periodic trends and characteristics of group 1 elements, also known as alkali metals. Keep in mind that predictions are based on general trends, and specific experimental data may vary.
A. Appearance: Alkali metals, including rubidium, have a silvery-white metallic appearance when freshly cut. However, they rapidly tarnish and become dull due to their high reactivity with air and moisture.
B. Hardness: Alkali metals are generally soft and can be easily cut with a knife. Rubidium is expected to be similar and have a low hardness.
C. Reaction with water: Alkali metals are highly reactive with water and produce hydrogen gas (H2) and an alkali metal hydroxide. Rubidium is expected to react vigorously with water, releasing hydrogen gas and forming rubidium hydroxide (RbOH). The reaction is exothermic and gives off heat.
2Rb(s) + 2H2O(l) → 2RbOH(aq) + H2(g)
D. Appearance and solubility of rubidium chloride: Rubidium chloride (RbCl) is an ionic compound. Ionic compounds generally form crystals with a regular arrangement of positive and negative ions. Rubidium chloride is a white crystalline solid.
In terms of solubility, alkali metal chlorides are generally soluble in water. Therefore, rubidium chloride is expected to dissolve in water, forming a colorless solution.
E. Electrical conductivity: Alkali metals, including rubidium, are highly conductive of electricity. This is because they have a single valence electron that is loosely held, allowing it to move freely and conduct electric current. Therefore, rubidium and its compounds, like rubidium chloride, are expected to exhibit high electrical conductivity.