Answer:The green growing on the penny of copper and the rust forming on the nail of iron are chemical changes. Boiling away salt water, scraping iron filings from a mixture of sand with a magnet, and breaking a rock with a hammer, are physical changes.
Explanation:
Answer: True
Air is a mixture of many things; it's not just Oxygen, but Hydrogen, Carbon, and Nitrogen as well are made up of air. Fun fact: Nitrogen is actually more abundant in air
Answer is: <span>the exact ratio of oxygen to octane for is 12.5 : 1.
</span>Balanced chemical reaction: C₈H₁₈ + 25/2O₂ → 8CO₂ + 9H₂O or multiply by 2:
2C₈H₁₈ + 25O₂ → 16CO₂ + 18H₂O.
There same number of atoms on both side of balanced chemical reaction: eight carbon atoms, eighteen hydrogen atoms and twenty five oxygen atoms.
The asthenosphere is directly below the lithosphere so the answer to your question is the asthenosphere, because the outer core is towards the center of Earth.