Answer:
A sample of water boils and releases gas.
Explanation:
Physical change is a change where no any chemical reaction takes place only the chemical composition of matter changes. It is a reversible process .
Burning of newspaper, rusting of iron, plant changes carbon dioxide and water into sugar (photosynthesis) are chemical reaction and irreversible process.
Answer:
When the energy is passed on from one trophic level to another, only 10 percent of the energy is passed on to the next trophic level.
Explanation:
Answer:
Option D describe the best this statement .
Explanation:
As velocity is the quantity which includes the rate of change as well as direction
Answer:For atoms and molecules, the width of spectral lines is governed mainly by the broadening of the energy levels of the atoms or molecules during interactions with surrounding particles and by the broadening of the spectral lines as a result of the Doppler effect.
Explanation:
This is an application of Boyle's law:
P₁V₁ = P₂V₂. we don't have to convert volume and pressure to standard forms. we can even use the pressure with mmHg
1 atm = 760 mmHg
V₂ = P₁V₁ / P₂ = 745 x 500 / 760 = 490 ml
Note that here we assume constant temperature
