Answer:
C. Soil
Explanation:
The choice with variable composition is the soil. Soil have many different composition.
- Soil is made up of minerals, organic matter , water and soil air.
- Soil minerals are derived from weathered bedrock materials that have been broken down into small pieces.
- Organic matter is derived from dead and decaying materials from plants and animals.
- All these materials combine together to form a soil.
Answer:
Adding Catalyst can Speed up a Chemical reaction
Answer:
A. a system that can be affected by the outside environment, by an exchange of matter or energy
Answer:
D. The relationship between volume and moles
Explanation:
Amedo Avogadro found the relationship between the volume of a gas and the number of molecules contained in the volume.
The law states that "equal volume of all gases at the same temperature and pressure contains the same number of molecules or moles".
Mathematically:
V ∝ n (P,T constant)
