A
On a field trip, your group finds a mineral that easily crumbles under pressure and cannot scratch your fingernail. What is its hardness on the Mohs scale?
a. 1
b. 2
c. 3
d. 4
Answer: a
a. 1
Explanation: A mineral that crumbles easily and cannot scratch a fingernail has a very low hardness, around 1 on the Mohs scale.
A scientist identifies a mineral sample that reflects light like a mirror. What kind of luster does it likely have?
a. Vitreous
b. Metallic
c. Waxy
d. Pearly
Answer: b
b. Metallic
Explanation: A mineral reflecting light like a mirror indicates a metallic luster.
During a class experiment, adding pressure and heat to granite transforms it into a rock with stripes. What rock has formed?
a. Marble
b. Quartzite
c. Gneiss
d. Basalt
Answer: c
c. Gneiss
Explanation: When granite is subjected to heat and pressure, it forms gneiss, which often has striped or banded textures.
You are handed a rock sample that feels rough and has visible sand particles. What type of rock is it?
a. Clastic sedimentary
b. Non-clastic sedimentary
c. Foliated metamorphic
d. Volcanic igneous
a. Clastic sedimentary
Explanation: Rocks with visible particles and rough textures typically form from compacted sediments.
A geologist is investigating a silicate mineral group. Which of these minerals is the most common in Earth’s crust?
a. Quartz
b. Hematite
c. Pyrite
d. Calcite
Answer: a
a. Quartz
Explanation: Quartz is the most common silicate mineral found in Earth's crust.
A volcanic eruption occurs in your area. After cooling, what type of igneous rock is most likely formed?
a. Plutonic rock with coarse grains
b. Volcanic rock with fine grains
c. Metamorphic rock with foliation
d. Sedimentary rock with layers
Answer: b
b. Volcanic rock with fine grains
Explanation: Volcanic rocks form from magma that cools quickly on the Earth's surface, leading to fine-grained textures.
While walking on a beach, you pick up a smooth, rounded rock with no visible crystals. What type of rock is this?
a. Igneous
b. Metamorphic
c. Clastic sedimentary
d. Non-clastic sedimentary
Answer: c
c. Clastic sedimentary
Explanation: Smooth, rounded rocks without visible crystals are likely sedimentary rocks formed through compaction of sediments.
You find a crystal that is smooth on certain faces but breaks randomly on others. Which property are you observing?
a. Streak
b. Hardness
c. Cleavage and fracture
d. Luster
c. Cleavage and fracture
Explanation: The property observed is the way the crystal breaks. Cleavage is smooth and flat, while fracture is rough and random.
You observe that water freezes and expands in the cracks of rocks, causing them to break apart. What process is this?
a. Physical weathering
b. Chemical weathering
c. Lithification
d. Regional metamorphism
Answer: a
a. Physical weathering
Explanation: Freezing and expansion of water in cracks are examples of physical weathering processes
A mineral breaks along smooth, flat surfaces and has a hardness of 2. What is this mineral?
a. Talc
b. Gypsum
c. Feldspar
d. Quartz
Answer: b
b. Gypsum
Explanation: Gypsum has a hardness of 2 and breaks along flat surfaces, showing cleavage.
While studying mineral groups, you learn about a mineral composed of CO₃²⁻ anions. To which group does it belong?
a. Silicates
b. Oxides
c. Sulfates
d. Carbonates
Answer: d
d. Carbonates
Explanation: Minerals with CO₃²⁻ belong to the carbonate group, such as calcite.
After visiting a marble quarry, your guide explains that marble originates from which parent rock?
a. Granite
b. Limestone
c. Sandstone
d. Shale
Answer: b
b. Limestone
Explanation: Marble is a metamorphic rock that forms from limestone through heat and pressure.
You are analyzing a mineral that looks like broken glass. Which luster category does it fall under?
a. Pearly
b. Waxy
c. Vitreous
d. Metallic
Answer: c
c. Vitreous
Explanation: Minerals that look like broken glass exhibit a vitreous luster.
While on a hike, you encounter a dark, fine-grained igneous rock. What is the rock most likely?
a. Granite
b. Basalt
c. Diorite
d. Gabbro
Answer: b
b. Basalt
Explanation: A dark, fine-grained igneous rock is most likely basalt, which forms from rapid cooling lava.
In an experiment, heat and pressure are applied to shale. What type of metamorphic rock could this produce?
a. Quartzite
b. Slate
c. Marble
d. Hornfels
Answer: b
b. Slate
Explanation: Shale subjected to low-grade metamorphism transforms into slate.
A scientist adds water to rock and observes it melting at a lower temperature. What caused the melting?
a. Increasing pressure
b. Addition of volatiles
c. Regional metamorphism
d. Decreasing temperature
Answer: b
b. Addition of volatiles
Explanation: Adding water (a volatile) lowers the melting point of rocks, causing partial melting.
Your teacher shows you a mineral sample with a fibrous appearance. What luster does it have?
a. Silky
b. Vitreous
c. Adamantine
d. Pearly
Answer: a
a. Silky
Explanation: A fibrous appearance indicates a silky luster.
In a deep-sea trench, rocks undergo immense pressure but little heat. What type of metamorphism occurs here?
a. Contact metamorphism
b. Regional metamorphism
c. Hydrothermal metamorphism
d. Dynamic metamorphism
Answer: d
d. Dynamic metamorphism
Explanation: Dynamic metamorphism occurs under intense pressure with minimal heat, common in deep-sea trenches.
A rock sample has alternating bands of light and dark minerals. What type of rock is this?
a. Foliated metamorphic
b. Non-foliated metamorphic
c. Clastic sedimentary
d. Intrusive igneous
Answer: a
a. Foliated metamorphic
Explanation: Alternating light and dark bands indicate a foliated metamorphic rock.
If magma crystallizes beneath the Earth's surface, what type of rock forms?
a. Plutonic igneous
b. Volcanic igneous
c. Sedimentary
d. Metamorphic
Answer: a
a. Plutonic igneous
Explanation: Magma crystallizing beneath the Earth's surface forms coarse-grained plutonic rocks.
A naturally occurring mineral group that makes up 92% of the Earth’s crust.
Answer: Silicates
The external shape of a crystal or aggregate of crystals.
Answer: Habit
A mineral property that describes how light reflects from its surface.
Answer: Luster
Rocks that are formed through the cooling and solidification of magma.
Answer: Igneous Rocks
The Earth subsystem that includes air and gases.
Atmosphere