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Task 2. Rebuild the following sentences from direct into indirect speech.
Translate the sentences into Ukrainian.
He asked,
1. “Why do some volcanoes form on the ocean floor, while others occur on the
continents?”
2. “What materials are associated with a volcanic eruption?”
3. “How do calderas form?”
4. “What changes in a volcanic landscape can be monitored to detect the movement
of magma?”
5. “Did the magma from which this rock formed likely originate in the mantle or in
the crust?”
6. “Would you expect all of the crystals in an intrusive igneous rock to be the same
size?”
7. “Was the magma likely a very high temperature magma or a fairly low temperature
magma?”
8. “What other minerals might make up the rest of this rock?”

Discussion

Task 1. Read and memorize the following words:
estimate – обчислити, вирахувати heft – зважити на руці
gravity – тяжіння, вага density – щільність, питома вага
magnetite – магнітний залізняк galena – галеніт, свинцевий блиск
matter – речовина, матерія pyrite - пірит, залізний колчедан
roughly - приблизно weight - вага

Task 2. Read the text. Translate it into Ukrainian. Talk about density and
specific gravity as important properties of matter. Transcribe the following words:
ratio, weight, pyrite, magnetite, galena, ore.

Density and Specific Gravity
Density, an important property of matter, is defined as mass per unit volume.
Mineralogists often use a related measure called specific gravity to describe the density
of minerals. Specific gravity is a number representing the ratio of a mineral’s weight to
the weight of an equal volume of water. Most common rock-forming minerals have a
specific gravity of between 2 and 3. For example, quartz has a specific gravity of 2.65.
By contrast, some metallic minerals such as pyrite, native copper, and magnetite are
more than twice as dense and thus have more than twice the specific gravity as quartz.
Galena, an ore of lead, has a specific gravity of roughly 7.5, whereas the specific gravity
of 24-karat gold is approximately 20. With a little practice, you can estimate the specific
gravity of a mineral by hefting it in your hand. Ask yourself, does this mineral feel
about as “heavy” as similar sized rocks you have handled? If the answer is “yes,” the
specific gravity of the sample will likely be between 2.5 and 3.

Task 3. Discuss the following:
1. Density.
2. Specific Gravity.

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