Elemental hydrogen (H, element 1), nitrogen (N, element 7), oxygen (O, element 8), fluorine (F, element 9), and chlorine (Cl, element 17) are all gases at room temperature, and are found as diatomic molecules.
Titanium, Lead, Potassium, and Silicon are solids at normal temperature.
Mercury and bromine (Br) are the only liquid elements at standard pressure and temperature (Hg).
<h3>What are chemical elements?</h3>
A chemical element is a species of atoms, including the pure substance made entirely of that species, that have a specific number of protons in their nuclei. Chemical elements, in contrast to chemical compounds, cannot be reduced by any chemical process into simpler molecules.
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Answer: Because of different redshift of cloud.
Explanation:
We are seeing absorption lines from clouds of gas that lie between us and the quasar, and therefore each cloud has a different redshift.
A quasar's spectrum is hugely redshifted. And most astronomers think this large redshift tells us about the distance to the quasar.
1. Physical Property
2. Chemical Change
3. Chemical Change
4. Chemical Property
5. Physical Property
6. Physical Change
7. Chemical Change
8. Physical Change
9. Chemical Change
10. Physical Property
11. Physical Property
12. Chemical Change
13. Chemical Change
14. Chemical Property
15. Chemical Change
Explanation:
Physical Property: A property of matter that can be seen, felt, tasted, smelled, or heard.
Physical Change: The change of an object of matter's physical property/properties.
Chemical Property: An element/object of matter's internal property/properties
Chemical Change: An element/object of matter's internal property/properties being altered or changed
Answer:
a sound wave is an electromagnetic wave
Answer:
Energy is the tendency to do work.
Explanation:
Energy unit is Joule
1 Joule means 1 kgm²/s²
Energy =Kinertic energy
=1/2 mv²
unit= kgm²/s²
So energy unit is derived unit.
