Laboratory Activity 4.3.1: Studying the reaction of alkali metals with oxygen |
Problem statement: How do lithium, sodium and potassium differ in reactivity with oxygen?
Hypothesis: Reactivity increases for the reaction between alkali metals and oxygen when going down Group 1
Variable:
» | Fixed variable : Oxygen | |
» | Manipulated variable : Type of alkali metal | |
» | Responding variable : Reactivity of the metal with oxygen |
Material: » Lithium » Sodium » Potassium » Phenolphthalein indicator » Oxygen » Water » Filter paper |
Apparatus: » Gas jar with cover » Gas jar spoon » Small knife » Test tube » Forceps » Bunsen burner |
► |
|
► |
|
► | Lithium, sodium and potassium react with oxygen to produce a white metallic oxide.
|
|||||||
► | The white solids which are formed are alkali metal oxides. | |||||||
► | The burning of lithium in oxygen is the least vigorous and the burning of potassium is the most vigorous. Thus, the reactivity of metals increases down Group 1. | |||||||
► | The metallic oxide dissolves in water to form an alkali. Thus, the solution turns phenolphthalein indicator to pink colour.
|
► | All Group 1 metals react with oxygen to form a metallic oxide which dissolves in water to produce an alkali. | |
► | The reactivity increases down the Group 1. | |
► | The hypothesis is accepted. |
⇲ For exercise(objective and subjective), download for free on Android OS. | ||
No comments:
Post a Comment