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.

Explanation:

The mineral need not occur always in a pure form.On purification we get the exact chemical composition.

The mineral always has a definite chemical composition which means the number of elements and types of elements in the mineral does not change.

Since the mineral has definite composition,the elements in the mineral has definite proportions.

The mineral can be a compound.So,there can be atoms from more than one element.

 It always contains certain elements.

It always contains elements in definite proportions.

Explanation:

A mineral is a naturally occurring, inorganic solid that has a crystal structure and a definite chemical composition

All the minerals are Naturally occurring i.e. they can not be man made. They are inorganic i.e. it can never come from something living. They occur as Solids i.e they have definite shape and volume. They have Crystal structure i.e they are formed by repeating units. They have definite chemical composition i.e they are made up of certain elements and the elements will always be present in a fixed ratio by mass.

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explanation:

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