Hurry pls what does it mean when a mineral has a definite chemical composition? select 2 choices.
it always occurs in pure form.
it always contains certain elements,
it cannot form from living or once living materials.
it always contains elements in definite proportions.
it cannot contain atoms from more than one element.

It always contains certain elements. ( second choice)

It always contains elements in definite proportions. ( fourth choice)

It means that it always contains certain elements and it always contains elements in definite proportions.

Explanation:

A mineral has five characteristics: definite chemical composition, naturally occurring, inorganic, solid and ordered internal structure.

Definite chemical composition means that every time a mineral is naturally created, its chemical formula is always the same, there are no modifications on the number of atoms of the elements that are contained in it, and those elements do not change.

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human impact on the environment can be seen in the deterioration of the !

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a. seed plant structure. 1. the three main plant organs are roots, stems, and leaves. a fourth kind of tissue, meristematic tissue, is responsible for plant growth. meristematic tissue is the only plant tissue that produces new cells by mitosis. plants can lose water out of their leaves as they exchange gases with the air

explanation: