An element is a pure substance
B:Oxygen and silicon
Explanation:
Most minerals on the earth's surface contains oxygen and silicon. Silicon and oxygen are the most abundant elements we find in the rock minerals on the earth surface.
- Silicon and oxygen forms the SiO₄⁻ tetrahedron through which several minerals are formed.
- These minerals built on the network of the tetrahedron are referred to as silicates.
- Several silicate minerals are known:
- Quartz
- Feldspars
- Olivine
- Biotite
- Pyroxene
Learn more:
Silicates brainly.com/question/4772323
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Answer:
The International System of Units (SI) is originated in France by frenches and originally was called a metric system of measurements. It provides definitions of various units of measurement such as weight, distance, electric current, temperature, and others which is widely accepted in the different fields of science and technology.
It is the system that is extended and derived from the french metric system of measurement is accepted in 1960 by convention 44 nation of the world to use particular unit of measurement worldwide to avoid confusion.
100 degree celcius and 0 degree Celsius
The number of atoms in a molecule can be calculated by adding all of the number of elements from the chemical formula. For chlorophyll, the chemical formula would be <span>C55H72MgN4O5 adding all the elements we have 137 atoms. Hope this answers the question.</span>