A Catalyst

question 45

Multiple Choice

A catalyst

• A)is an H⁺-yielding molecule.
• B)is an acid.
• C)is an alkali.
• D)increases the speed of a chemical reaction.

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Definitions:

Stratosphere

The stratosphere is a layer of the Earth's atmosphere located above the troposphere, characterized by a slight temperature increase with altitude and the presence of the ozone layer.

Ozone

A molecule composed of three oxygen atoms, found in the Earth's stratosphere, where it plays a critical role in protecting living organisms from ultraviolet radiation.

Lichen

A symbiotic organism composed of a fungus and a photosynthetic partner, typically an alga or cyanobacterium, found on rocks, trees, and soil.

Mutualistic Relationship

A type of symbiotic relationship where both organisms involved benefit from their interaction.