Description: Na and Mg metals react with oxygen to produce basic oxides that turn universal indicator purple (basic). Carbon on the other hand reacts with oxygen to produce an acidic oxide that turns universal indicator orange (acidic).

Concept: Most metals react with oxygen to produce basic oxides. Most non-metals react with oxygen to produce acidic oxides.

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Description: Lithium, sodium, and potassium metals are sliced and then a small sample of each is reacted with water.

Concept: The alkali metals are soft and silvery. They are also the most reactive metals having the lowest ionization energies. They react readily with water, lithium being the least reactive and potassium the most.

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Description: Samples of Mg and Ca are displayed. Mg and HCl produce less bubbles than Ca and HCl. Mg and H2O produces less hydroxide and therefore less pink with phenolphthalien than Ca and H2O.

Concept: The alkaline earth metals are less reactive and harder compared to the alkali metals. They do not react as readily with water. Mg is less reactive than Ca.

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Description: Many samples of elements are available to be displayed in class.

Concept: An element is a substance that cannot be decomposed by any chemical reaction into simpler substances; a type of matter composed of only one kind of atom, each atom of a given kind having the same properties.

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Description: Small cards showing each element and their atomic number are arranged to form the periodic table.

Concept: When the elements are arranged by atomic number, their physical and chemical properties such as atomic radius, ionization energy and electron affinity, vary periodically.

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Description: He, Ne, and Ar discharge tubes show different colors.

Concept: The electrons of an element are excited in a discharge tube. As these excited electrons fall back from one energy level to another, they will emit photons of light. These photons will have different colors depending on the element and its discrete energy levels. That is, different wavelengths of light (colors) will be emitted when the electrons of different elements go down the steps between their energy levels. Each element will have its own set of steps, therefore each will have its own color or set of colors.

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Description: Samples of Cl2 gas, Br2 liquid, and I2 solid are displayed in round 1 L glass bulbs.

Concept: When excited, electrons of different halogens emit different colors.

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Description: The space filling model is compared to the ball and stick model.

Concept: The atoms of different elements have particular sizes. Space filling molecular models show the relative atomic sizes of the atoms of the molecule

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Description: A vial containing an ionic compound containing a paramagnetic metal is hung from a string from a bar on a ring stand in between the gap in a gap magnetic and the vial sticks to one of the sides of the magnet. Repeat with a diamagnetic metal and the vial just sits in the middle of the gap, not sticking to either side.

Concept: Paramagnetism is the tendency of a species with unpaired electrons to be attracted by an external magnetic field. A species with all of its electrons paired exhibits diamagnetism and is slightly repelled by a magnetic field.

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Description: Models of different atomic orbitals are displayed.

Concept: The orbits of electrons change depending on their energy level.

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Description: We have a collection of discharge tubes of various sizes. Most are small, but we have a few that are large enough that their atomic line spectra can be viewed through a hand held diffraction grading from the balcony of the large auditorium. If desired, the view of any atomic spectra through a spectroscope can be projected onto a television screen.

Concept: When the gas of an element is heated in a lamp and the resulting light is spread out with a diffraction grading, a line spectrum will be observed showing only certain colors of wavelengths related to the energy levels of the atom of the element.

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Description: Five different metal ions are passed into the burning gas in a Bunsen burner. Each metal as it is burned will emit a different color.

Concept: When an element is burned, the electrons will be excited. Then as these electrons fall back from one energy level to another, they will emit photons of light. These photons will have different colors depending on the element and its discrete energy levels.

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Description: Different salts are burned within glass Petri dishes. Sodium burns orange, potassium - purple/blue, barium - green, copper ? blue/green, and lithium or strontium ? red

Concept: When an element is burned, the electrons will be excited. Then as these electrons fall back from one energy level to another, they will emit photons of light. These photons will have different colors depending on the element and its discrete energy levels.

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Description: : Different salts are burned within glass Petri dishes. Sodium burns orange, potassium - purple/blue, barium - green, copper ? blue/green, and lithium or strontium ? red.

Concept: When an element is burned, the electrons will be excited. Then as these electrons fall back from one energy level to another, they will emit photons of light. These photons will have different colors depending on the element and its discrete energy levels.

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Description: Liquid oxygen is poured or dripped into a gap magnet and seen to stick to the poles.

Concept: Liquid oxygen?s MO has two unpaired electrons, making it paramagnetic and susceptible to a magnetic field.

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Description: Six, colored solutions are shown to the students while a color wheel and a visible light spectrum is projected onto the wall. The students are shown transparencies of six different absorbance spectra, and are asked to aid in predicting which spectrum corresponds to which solution.

Concept: If a solution appears to be red, then it is reflecting red light and absorbing the color of light that lies across from red on the color wheel.

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Description: Spectacular colors are produced as various balloons are ignited.

Concept: As the hydrogen is combusted, electrons in metal salts concealed within the balloons are excited to higher energy levels. As the electrons fall back to lower energy levels, photons are emitted. The color of the burst will depend on the metal salt used and the corresponding wavelength of light emitted.

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Description: The colors of various transition metals can be displayed on the overhead.

Concept: Ions of the transition elements exist in aqueous solution as complex ions. Transition-metal compounds are often colored. The color results from the transition of electrons between the two closely spaced d orbitals. The transitions are due to the electric field of the compound's ligands.

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