Answer:
Evaporation
Explanation:
Evaporation involves a liquid becoming a gas and sublimation is the change of a solid directly to a gas. Phase changes require either the addition of heat energy or subtraction of heat energy .
Answer:
1.62
Explanation:
From the given information:
number of moles of benzamide 
= 0.58 mole
The molality = 

= 0.6837
Using the formula:

where;
dT = freezing point = 27
l = Van't Hoff factor = 1
kf = freezing constant of the solvent
∴
2.7 °C = 1 × kf × 0.6837 m
kf = 2.7 °C/ 0.6837m
kf = 3.949 °C/m
number of moles of NH4Cl = 
= 1.316 mol
The molality = 
= 1.5484
Thus;
the above kf value is used in determining the Van't Hoff factor for NH4Cl
i.e.
9.9 = l × 3.949 × 1.5484 m

l = 1.62
What I can’t understand I’m American
<h2>
ANSWER:</h2>
D.No, she is not accelerating because her speed is constant.
<h2>
EXPLANATION:</h2>
The rate of change of velocity with respect to time is known as acceleration.
acceleration =change in velocity/time
As she is running at constant speed and there is no change in velocity so she is not accelerating.
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.