It is a physical change when cream mixes with
coffee, it changes the color of the coffee. When you add more or less cream there
is a color change depending on the consistency of cream. The
properties are not changes and a no new compound is formed as in chemical
change with a reaction of two compounds, a new compound is formed with
different properties. So it is a physical change.
Answer: Although the best-known cause of a mass extinction is the asteroid impact that killed off the non-avian dinosaurs, in fact, volcanic activity seems to have wreaked much more havoc on Earth's biota. Volcanic activity is implicated in at least four mass extinctions, while an asteroid is a suspect in just one. Examples, of mass extinctions are Permian extinction of marine species, and Cretaceous extinction of various species, including dinosaurs.
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Answer:</h3>
The gas obeys the Boyle's law
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Explanation:</h3>
- According to Boyle's law, the volume of a fixed mass of a gas and the pressure are inversely proportional at constant absolute temperature.
- That is;
- Therefore,
, where k is a constant - At varying volume and pressures while keeping absolute temperature constant; k = P1V1 =P2V2
In this case, we are given;
Initial Volume of 13.0 L at initial pressure of 1.0 atm
New volume of 6.5 L at new pressure of 2.0 atm
But, K = PV
Therefore,
k1 = P1V1
= 1.0 atm × 13.0 L
= 13 atm.L
k2 = P2V2
= 2.0 atm × 6.5 L
= 13 atm.L
Thus, k1=k2
Thus, the gas obeys the Boyle's law
