Rocks and Minerals by UTH Rocks and Minerals by UTH    

Lesson 14: Chemical Properties

Directions

Study the lesson for one week.

Over the week:

• Read the lesson.
• Review the synopsis.
• Recite aloud the vocabulary words and their definitions.
• Study the rock and mineral of the week.
• Complete the enrichment activities.
• Study the review questions.

Synopsis

Chemical properties include any properties of a substance that become evident during a chemical reaction. Chemical reactions may occur when substances are combined, when a substance breaks down into multiple products, or when substances are burned. Chemical reactions may change the chemical formula of a substance by breaking or forming chemical bonds between atoms and change the numbers and identities of its elements. Evidence of chemical reactions include change of color (e.g. metallic silver to yellow) and change of state (e.g. solid to liquid).

Vocabulary

Chemical Bond: Any of several attractive forces that serve to bind atoms together to form molecules.
Chemical Reaction: A process, typically involving the breaking or making of interatomic bonds, in which one or more substances are changed into others.
Buoyancy: The upward force on a body immersed or partly immersed in a fluid.

Rock or Mineral of the Week

• Halite, commonly known as salt, is a mineral most people are familiar with as a food seasoning.
• Salt is made from the elements of sodium (Na) and chlorine (Cl).
• When separate, sodium (Na) is a silver metal and chlorine (Cl) is a yellow gas.
• Both sodium (Na) and chlorine (Cl) are poisonous to humans.
• However, when sodium and chlorine form a chemical bond, the chemical reaction creates the white, edible solid called salt (NaCl).

Physical Characteristics

• Color: White when pure
• Hardness: 2.5
• Luster: Vitreous
• Cleavage: Perfect cubic
• Streak: White
• Tenacity: Brittle

Location

• All over the world including the Sifto Salt Mine in Canada

Interesting Facts

• Some salt mines are located underground, including underneath lakes. The Sifto Salt mine is located under Lake Huron in Canada.

• Halite, or salt, has a cubic crystal structure.

• Salt is found in the Earth's oceans as well as salt lakes including the Great Salt Lake in Utah, United States.
• The Great Salt Lake is so salty fish cannot live in its waters.
• The salt in the Great Salt Lake increases buoyancy, making it very easy for people to float on their backs in its salty waters.

Enrichment

Activity 1: Narrate the Lesson

• After reading or listening to the lesson, narrate the lesson aloud using your own words.

Activity 2: Can You Find It?

Find the following elements on the periodic table:

• Sodium (Na)
• Chlorine (Cl)
• In which group and period is chlorine (Cl)?

Activity 3: Map the Lesson

• The Great Salt Lake is found in the state of Utah.
• Find Utah (UT) on the map of the United States.

Activity 4: Take a Nature Walk

• Embark on a nature walk.
• Collect one rock or mineral specimen.
• Use the gathered specimen to create the field book entry.

Activity 5: Complete a Field Book Entry   

After your nature walk, complete page 6 in 'Fifth Grade Science Rocks and Minerals Notebook Pages.'

Review

Question 1

Is the reaction of sodium metal and chlorine gas to create salt a physical change or a chemical change?

1 / 4

Answer 1

The reaction of sodium metal and chlorine gas to create salt is a chemical change.

1 / 4

Question 2

Describe something about salt (NaCl).

2 / 4

Answer 2

Salt (NaCl) is a white solid found in oceans and some lakes. Salt is a common seasoning for food.

2 / 4

Question 3

Is a salt (NaCl) a compound?

3 / 4

Answer 3

Yes, salt (NaCl) is a compound consisting of more than one type of element.

3 / 4

Question 4

How many different elements does salt (NaCl) contain?

4 / 4

Answer 4

Salt (NaCl) contains two types of elements - sodium (Na) and chlorine (Cl).

4 / 4

❮ ❯

1. Is the reaction of sodium metal and chlorine gas to create salt a physical change or a chemical change? The reaction of sodium metal and chlorine gas to create salt is a chemical change.
2. Describe something about salt (NaCl). Salt (NaCl) is a white solid found in oceans and some lakes. Salt is a common seasoning for food.
3. Is a salt (NaCl) a compound? Yes, salt (NaCl) is a compound consisting of more than one type of element.
4. How many different elements does salt (NaCl) contain? Salt (NaCl) contains two types of elements - sodium (Na) and chlorine (Cl).

References

'Halite.' Wikipedia. en.wikipedia.org/wiki/Halite. n.p.

Cited Physical Properties. Geology.com. geology.com/rocks. n.p.