Because their atoms and molecules are held together firmly by the strong inter molecular forces
Answer:
a. friction
Explanation:
What is a common unbalanced force acting in motion? Common forces that are often unbalanced include the force of gravity and applied forces. When these forces are unbalanced, objects accelerate, change their position and find new configurations for which all forces are again balanced.
Friction is a kind of force.
It is called nuclear energy.
Answer:
ΔE negative,ΔE positive,ΔE positive
Explanation:
Internal energy change of a system is positive when the system acquires energy from outside and internal energy change is negative when energy is being liberated from the system.
a Sweat evaporates from skin,cooling the skin ΔE is negative as heat energy is liberated through evaporation of sweat.
b A balloon expand against an external pressure ΔE positive because external energy is required to expand the balloon.
c An aqueous chemical reaction mixture is warmed with an external flame ΔE is positive because heat energy is provided by the external flame to warm the aqueous chemical reaction.
Answer:
c
Explanation:
The first ionization energy decreases because the outermost
electron is farther from the nucleus.
