Answer:
the formation and evolution of stars and galaxies
Explanation:
One of the topic an astronomer will most likely study is the formation and evolution of stars and galaxies.
Astronomers are scientists that studies the universe, its components and how it works.
- An environmental scientist is concerned with pollution on a local river.
- A civil engineer is specializes in designing structures that can withstand earthquake damage.
- A biologist will observe the movement of dolphins.
Answer:
charles's law.by seeing how changes in temperature affect the pressure of the gas
Answer:
Pb(NO3)2 + 2NaCl = 2NaNO3 + PbCl2
Answer:
The order is
Quartz > Calcium > Ammonia > Chlorine
Explanation:
Among given compounds
Quartz is a covalent compound with extensive bondings and thus it will have highest melting point
Calcium is a metal so it will have strong metallic bonds thus will have high melting point, however less than quartz.
ammonia is a polar molecule with weak hydrogen bond as intermolecular interactions thus will have higher melting point than chlorine
chlorine is a non polar molecule with weak intermolecular london dispersion forces.