The pressure of a gas is the force that the gas exerts on the walls of its container. When you blow air into a balloon, the balloon expands because the pressure of air molecules is greater on the inside of the balloon than the outside. Pressure is a property which determines the direction in which mass flows.
Answer: (3) molecules have different molecular structures.
Explanation:
1) Oxygen (O₂) and ozone (O₃) are allotropes of each other.
2) Allotropes are different structural forms of a same element with different structures and properties, when they are in the same state: solid, liquid, gas.
3) The bonds is what define the structure and properties of the substances, so since O₂ has only two bonds and O₃ has three bonds, the properties and behaviors of the element are different.
4) Other example of allotropes are graphite and diamond: two different forms of carbon. Both, graphite and diamond are formed only by carbon atoms, but they are bonded differently so, as you know, diamond and graphite have different properties: graphite is very soft while diamond is one of the hardest known substances.
C₀=2 mol/l
c₁=0.400 mol/l
v₁=100.0 ml = 0.1 l
c₁v₁=c₀v₀
v₀=c₁v₁/c₀
v(H₂O)=v₁-v₀
v₀=0.1*0.400/2=0.02 l = 20 ml
v(H₂O)=100 - 20 = 80 ml
It is necessary to mix 20 ml of the feed solution and 80 ml of water.
7. Large Intestine and chemical digestion
8.stomach
9.capillaries
4.neurons
hopefully this is correct