a. The unit cell is the smallest group of atom which have overall symmetry of a crystal, and from which is the entire letters can be buled built up by repetition in 3 dimensions.
b. The volume(v) of the unit cell is equal to the cell edge length (a)cubed.
c. density of polonium is 9.32g/cm3.
Answer: Well!
Explanation: I was going to answer D but fverdell82156 got to it first! So I have to agree with him! It is D!
Answer:
Physical Change
Explanation:
The bush is changing shapes, not changing what it is.
Answer:
The particles move faster and are far apart
Explanation:
A substance may exist in three states of matter; solid, liquid and gas.
In the solid state, there is very strong intermolecular forces between the particles of the substance. They can only vibrate or rotate about their mean positions but can not translate.
In the liquid state, the particles of the substance have a greater degree of freedom than in the solid. The magnitude of intermolecular forces is lower than in solids, the molecules can move at low speeds.
In a gas, the molecules are separated from each other with negligible intermolecular interaction hence they move at very high speed.
Therefore, for the water gas particles in the air above the cup; the particles move faster and are far apart.
Answer:
The heat of the reaction is 105.308 kJ/mol.
Explanation:
Let the heat released during reaction be q.
Heat gained by water: Q
Mass of water ,m= 1kg = 1000 g
Heat capacity of water ,c= 4.184 J/g°C
Change in temperature = ΔT = 26.061°C - 25.000°C=1.061 °C
Q=mcΔT
Heat gained by bomb calorimeter =Q'
Heat capacity of bomb calorimeter ,C= 4.643 J/g°C
Change in temperature = ΔT'= ΔT= 26.061°C - 25.000°C=1.061 °C
Q'=CΔT'=CΔT
Total heat released during reaction is equal to total heat gained by water and bomb calorimeter.
q= -(Q+Q')
q = -mcΔT - CΔT=-ΔT(mc+C)

Moles of propane =
0.0422 moles of propane on reaction with oxygen releases 4.444 kJ of heat.
The heat of the reaction will be:
