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:
Science doesn't make moral judgments, doesn't make aesthetic judgments, doesn't tell you how to use scientific knowledge, doesn't draw conclusions about supernatural explanations. So that's why I think it has limitations.
2 hydrogen and 1 oxygen makes water
Answer:
KE = 1/2*m*v^2
KE = 1/2*150kg*(20 m/s)^2
KE = 75kg * 400m²/s²
KE = 30,000 kg*m²/s²
KE = 30,000 N*m
KE = 30,000 J
Explanation:
Hope this helped.
A brainliest is always appreciated.
<span>The addition and subtraction of negatively charged electrons can easily change an atom’s charge, because they perpetually spin in valence shells outside the nucleus. It is easier for a neighboring atom to share or steal an electron rather than a positively charged proton, which is found in the nucleus. It requires a strong energy input to split a proton free from other protons and neutrons. thus, the atoms lose or gain electrons from neighboring ones and become what is known as "ions". Hope it helped!</span>