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: Melatonin has been used safely for up to 2 years in some people. However, it can cause some side effects including headache, short-term feelings of depression, daytime sleepiness, dizziness, stomach cramps, and irritability. Do not drive or use machinery for four to five hours after taking melatonin.
An imaginary line joining a planet and the sun sweeps out an equal area of space in equal amounts of time. Thus, the speed of the planet increases as it nears the sun and decreases as it recedes from the sun.
Why does magma composition change during fractional crystallization? Different elements in the magma form crystals at different rates, leaving behind more of the unused elements. ... The crystals are denser than the magma.
