These are different parts of a question. I just need their brief answers in two

Question

These are different parts of a question. I just need their brief answers in two or three lines in proper way. Thanks

Question:2 a. What is cleavage? What causes it? Why doesn't quartz have cleavage? b. Can a mineral lacking cleavage still have crystal faces? Explain. c. How many minerals (not elements) compose most of Earth's crust? d. How many elements compose the minerals that make up most of Earth's crust? e. Which mineral can be scratched with a knife and effervesces (fizzes) in dilute hydrochloric acid (HCI) or even in warm vinegar? f. What mineral is "fools gold? What is the chemical composition (formula) of that mineral? g. Of all the minerals in Earth's crust, 95% belong to a group called "silicates." What is the difference in meaning between the terms silicate and silicon? h. Silicates are further divided into 2 groups: nonferromagnesian silicates (light in color, low in specific gravity) and ferromagnesian silicates (dark in color, high in specific gravity). What is the basic cause of the difference in color and specific gravity between these two groups? in ie gravity between these two grouans i. What is the difference between a rock and a mineral?

Explanation / Answer

a. Cleavage is a weak plane where crystal tends to break due to its structure of crystal lattice. Alignment of weaker bonds in a plane of crystal lattice causes cleavage formation but no loss of cohesion will be there. Quartz has no cleavage because silicon is bonded covalently with oxygen very strongly which don't break.

b. Yes, as Crystal faces are formed at surface of the crystal during formation by twinning etc,. But cleavage planes are formed in internal structure of crystal by weaker bonds or due to stress. Cleavage planes are parallel to crystal faces always.

C. Most of the crust is composed of silicate minerals. Feldspar dominate among which plagioclase composition is high and then alkali feldspar. Second most is quartz mineral, then pyroxenes, amphiboles, micas and clay minerals.

D. As stated above these minerals consists elements which are dominant those are in order oxygen, silicon, aluminum, iron, calcium, magnesium, sodium and potassium.

E. Calcite is the mineral scratched by knife as it has hardness 3 on mohs scale and it produces effervescence on reacting with hcl or warm vinegar due to dissolution of carbonate and releases CO2.

F. Pyrite is called as fools gold generally due to its similar appearance of gold. It is an iron sulphide. FeS2.

G. Silicates are structures formed by network of silicon and oxygen with other elements in the crystal lattice. But silicon alone is an element but not a compound.

H. As ferromagnesian silicates have high iron and magnesium content they have high specific gravity due to higher atomic mass of iron. These are dark in color due to color imparted by iron.

I. Mineral is a basic component of rock. Rock is constituted with one or more minerals and rock is defined or named on the basis of dominant minerals and their composition.

Related Questions

Navigate

• Browse (All)
• Browse T
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.