To. Normal Matter is composed of……. Atoms differ in the number of “pieces” ( Protons,...

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Transcript of To. Normal Matter is composed of……. Atoms differ in the number of “pieces” ( Protons,...

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Normal Matter is composed of…….

Atoms differ in the number of “pieces” ( Protons, Neutrons and Electrons) that they have inside of

them.

Atoms with certain consistent characteristics are called….

matter that is made up of atoms…matter that is made up of atoms (or one atom) that have the same number of Protons in their nucleus.

But!!!Not all atoms of the

same element are the same, either.

Atoms of the same element that have different numbers of neutrons in their nuclei are

called….

Certain isotopes of elements are unstable, or radioactive.

(example: Carbon-14 and

Uranium-238)

These radioactive isotopes of elements allow us to do absolute-age dating!

Most substances on Earth are not pure elements but rather….

???

What is a Compound?

A Compound is…..

A substance made from two or more different elements that have been chemically combined.

A Mixture, on the other hand, is…

A substance made from two or more different elements that have not been chemically combined, and which can be separated by physical means

Elements by themselves are much

less common than Compounds, because they tend to combine

with each other to form Compounds.

Elements and Compounds in their solid form make up…

What is a Mineral?

A Mineral is a naturally occurring Inorganic Solid with a

definite chemical composition and a crystalline structure.

That means that…

•It can’t be organic in origin•It can’t be a liquid and..•It has to have a crystal structure

Lets put that in a list format.

1. Minerals are a naturally occurring substance.

2. Minerals are solids.

3. Minerals have a definite chemical composition.

4. The atoms that make up minerals are arranged in an orderly pattern (They form crystals).

5. Minerals are inorganic. (They were never alive.)

How many different minerals are there on Earth???

Answer:About 4,000

More than 90% of all of the minerals in the Earth’s Crust,

however, are made up of compounds containing Silicon

and Oxygen, the two most abundant elements on Earth.

And…..The percent composition of Silicate

Minerals in an igneous rock determine a lot of the characteristics of that rock and

the magma that formed it.

High Silica content forms light-colored rocks.

While lower (but only by about 25%) Silica content forms

darker-colored rocks.

How do Minerals Form???

1. Minerals form in cooling magma chambers

Different types of minerals crystallize at different

temperatures

Decreasing temperature

Mineral formation in a Magma Chamber

Bowen’s Reaction Series

Olivine

Pyroxene

Peridotite- Mostly Olivine

Gabbro- Pyroxene and Olivine

Andesite- Hornblend and Biotite? and Plagioclase Feldspar

Potassium Feldspar

Quartz

Pink Granite

Mineral Fractionalization in a Magma Chamber

2. Metamorphic Minerals:Some minerals occur as the

result of Recrystallisation and Reaction within existing rocks which produces new minerals

in response to changes in

and

3. Some types of minerals form as water containing dissolved

ions slowly evaporates.Salt deposits

How long does it take for minerals to form??

• Minerals in solution in water can form relatively quickly when the water evaporates.

• Minerals in magma can form as quickly as the magma/lava can crystallize (lava can cool in minutes, while magma can take thousands of years).

A Crystal is….

A regular geometric solid with smooth surfaces called….

The orderly arrangement of ions, molecules, or atoms, in any

mineral determines the shape of its crystals.

Although there are thousands of different types of minerals, their crystals come in six basic types

of shapes

Minerals are identified and classified by visual inspection, and

by performing simple tests to determine their physical properties

Only 30 of the 4,000 known minerals are common.

These 30 minerals are known as the rock-forming minerals

Most rock-forming minerals are…

The percent composition of Silicate minerals in a rock determines the type of rock it is.

Rocks that have a high percentage of Silicates are light in color, and

are called Felsic rocks.

Rocks that have a low percentage of Silicates are dark

in color, and are called Mafic rocks.

Rocks are often made of several different minerals.

Minerals are most often identified by inspecting their

Physical and Chemical properties.

Color is the most easily observed, but least reliable property of a mineral for identification.

This is because the color of many minerals varies with the kind of impurities in the mineral.

Luster is the way in which a mineral shines in the light.

Types of Luster

Streak is the color of the powder left on a streak plate when a mineral is rubbed on it.

Streak is much more reliable than color because, although the color of a mineral changes, its streak does not.

Cleavage is the tendency of a mineral to split in a particular direction.

“Sheety” Cleavage

Feldspars always cleave readily at or near right angles.

Fracture is the tendency of a mineral to break in directions other than along crystal faces or cleavage surfaces.

Conchoidal or shell-like fracture

Fibrous facture

Hardness is the resistance of a mineral to being scratched.

The Mohs Hardness Scale is one of the most effective tool for identifying minerals.