Crystal Properties and Characteristics in Science

The video tutorial explains the physical properties of minerals, including external crystal form, cleavage, fracture, lustre, colour, streak, transparency, structure, hardness, and specific gravity. It highlights how these properties are determined by the internal molecular arrangement and how they affect the mineral's appearance and functionality. The tutorial also emphasizes the importance of understanding these properties for practical applications in everyday life.

What determines the external shape of a crystal?

• The external environment

• The internal arrangement of molecules

• The temperature during formation

• The pressure applied to the crystal

How does cleavage differ from fracture in crystals?

• Cleavage occurs along smooth planes, fracture in non-plane areas

• Cleavage is rough, fracture is smooth

• Cleavage occurs in non-plane areas, fracture in plane areas

• Cleavage is caused by external forces, fracture by internal forces

What property of a mineral is described by its shine or polish?

• Colour

• Hardness

• Lustre

• Transparency

How do humans perceive the colour of a mineral?

• By the mineral's temperature

• By the mineral's size

• By the mineral's weight

• By the wavelengths of light absorbed and reflected

What is the streak of a mineral?

• The colour of the mineral when powdered

• The shine of the mineral

• The hardness of the mineral

• The colour of the mineral in its natural state

What determines whether a mineral is transparent, translucent, or opaque?

• The mineral's hardness

• The mineral's colour

• The mineral's thickness

• The mineral's weight

What is the crystal lattice?

• The external shape of a mineral

• The internal arrangement of molecules in a crystal

• The colour pattern of a mineral

• The hardness scale of a mineral

What does the Mohs scale measure?

• The specific gravity of a mineral

• The transparency of a mineral

• The colour of a mineral

• The hardness of a mineral

Which mineral is the hardest according to the Mohs scale?

• Talc

• Gypsum

• Quartz

• Diamond

How is specific gravity of a mineral determined?

• By comparing the mineral's weight to an equal volume of air

• By observing the mineral's colour

• By comparing the mineral's weight to an equal volume of water

• By measuring the mineral's hardness