Chemistry Chemical Reactivity Lab: Periodic Trends

Hypothesis

Step One: Read the Lab out loud in your groups.

Step Two: Come up with a hypothesis…..what do you think will happen at the end of the lab.

Introduction:• The periodic table, arranged according to the electron

configurations of the elements, can be used to predict the physical and chemical properties of elements and their compounds. The vertical columns of the table are referred to as groups; the horizontal rows are called periods. General trends exist within groups and periods on the periodic table. Some of these trends include atomic size, ionization energy, electronegativity, density, melting point, and chemical reactivity. For example, the atomic size tends to increase as you move down a group and decrease as you move across a period. As you move down a group, the number of energy levels increase, so there are more “clouds” around the nucleus. As you move across a period, the energy level remains constant, but the number of protons (atomic number) is increasing. The positive nuclear charge is increasing which pulls the electrons closer to the nucleus and therefore reduces the atomic radius.

Purpose:

• How can chemical reactivity be investigated as a function of an element’s location within a group and period?

Materials:• Read the Procedure then list all

materials in your lab notebook.

• This should be done as a group. Everyone in the same group should have the same things written until you write the conclusion.

Procedure:

• Write a Step by Step summary of the procedures:

For example.

Step One: Observe the reactivity of lithium , sodium, potassium

Create A Data TableMetals Water HCl Reactivity

RankingObservations

Observations

• Step One: Describe the way the metal looks

• Step Two: Describe the way the metal looks in water …in HCl (hydrochloric acid)

• Step Three: List the reactivity ranking of the metals. Most reactive will be five and least will be one.