An Endothermic change is a process in which there is absorption of energy.
-Condensation is the transformation from a gas to a liquid. So the water molecules releases energy while condensing, so condensation is exothermic (opposite of endothermic, it's the release of energy)
-Vaporization is the transformation from a liquid to a gas. When you heat water to evaporate it, you're giving energy to the water molecules. And when they absorb this energy, they transform to a gas. Which means that Vaporization is endothermic.
-Deposition is the transformation from gas directly to solid without passing by the liquid phase. Same as the condensation, but the water molecules release even more energy to directly become Solid. So deposition is exothermic.
-Freezing is the transformation from a liquid to a solid. During this phase, water molecules releases energy to its surrounding. So freezing is exothermic.
We can conclude that Vaporization is endothermic, because it's absorbing energy to transform from liquid to gas, while condensation, deposition and freezing are exothermic because they release energy to transform.
Hope this Helps! :)
Answer:
Dalton's atomic theory was the first complete attempt to describe all matter in terms of atoms and their properties.
Dalton based his theory on the law of conservation of mass and the law of constant composition.
The first part of his theory states that all matter is made of atoms, which are indivisible.
The second part of the theory says all atoms of a given element are identical in mass and properties.
The third part says compounds are combinations of two or more different types of atoms.
The fourth part of the theory states that a chemical reaction is a rearrangement of atoms.
Parts of the theory had to be modified based on the existence of subatomic particles and isotopes
Answer:
158g
Explanation:
To calculate the "weight" (mass) of ethyl alcohol, we have to use this formula:
- Density will have units of gmL when dealing with a liquid or units of gcm3 when dealing with a solid.
The mass has units of grams, g.
The volume will have units of mL or cm3
We are given the density and volume, both of which have good units so all we have to do is rearrange the equation to solve for the mass:
density×volume=massvolume×volume
Density×Volume = Mass
0.789gmL×200.0mL
Thus, ethyl alcohol weighs 158g.
In order to compress a gas, high pressure should be met. <span>There are three major groups of compressed gases stored in cylinders: liquefied, non-liquefied and dissolved gases. In each case, the pressure of the gas in the cylinder are high. Hope this helps.</span>
