The average speed is 75 Km per hour. Remember the equation for speed is Speed = Distance divided by Time
Answer:
The two types of collisions are :
Type a)
<u>Elastic collision</u>
Type b)
<u>Inelastic collision</u>
Explanation:
Collision : It is the event when two bodies collide with each other for small period of time.
During collision , the bodies exert force to each other.
Example :
When boxer hits with punches .
When bat hits the ball in cricket match.
So, collision is short duration interaction of two objects. When the objects collides , there is change in their velocity.
All collision follow law of conservation of momentum . Their type is decided by , whether they follow conservation of energy also.
<u>Compare and contrast the two types</u>
a) Elastic collision : Those collision in which no loss or gain of kinetic energy will occur. They follow conservation of kinetic energy. Example : ideal gaseous molecule
b) Inelastic collision : Those collision in which Change in kinetic energy will occur. They do not follow conservation of kinetic energy.Almost all conservation are inelastic.
Here Kinetic energy get converted into other form of energy.
Explanation:
As per the Hess’s law of constant heat summation, the heat absorbed or evolved in a given chemical equation is the same whether the process occurs in one step or several steps.
Hence, according to this law the chemical equation can be treated as ordinary algebraic expression and can be added or subtracted to yield the required equation. This means that the enthalpy change of the overall reaction is the sum of the enthalpy changes of the intermediate reactions.
..........(1)
..............(2)
The final reaction is as follows:
.............(3)
Therefore, adding (1) and (2) we get the final equation (3) and value of 
at 298 K will be as follows.
= 
+ 
= -314 kJ + (-80) kJ
= -394 kJ
Thus, we can conclude that 
at 298 K for the given process is -394 kJ.
The density of the gold is 19.3 grams/cc so each cc weighs 19.3grams. Now we can obtain the volume of gold from the given dimensions ie 4.72x8.21x3.98= 154.23 cc. So for the answer, just multiply the volume or 154.23 x 19.3= 2976.6 grams is the answer.
