Intermolecular Forces
What state of matter has the strongest intermolecular forces?
Solid
What happens to the temperature during a phase change?
The temperature remains constant during a phase change. (the plateaus)
What is an example of a chemical property?
Reactivity, Toxicity, Acidity, Flammability
Calculate the density of a substance with a mass of 50g and a volume of 25cm³.
D=2 g/cm3
Define brittleness.
Brittleness is the tendency of a substance to crack or break easily.
Explain the molecular motion in a solid.
The particles in a solid have the least motion and vibrate in fixed positions.
Identify the phase change occurring between E → F.
Refer to Diagram
The substance is in a gaseous state.
Define solubility.
Solubility measures a substance’s ability to dissolve into a given liquid.
How do you find the mass of a gold bar with dimensions 1 cm x 2 cm x 10 cm and a density of 19.3 g/cm3
Calculate volume first: V=1×2×10=20cm3 Then use density: m=D×V=19.3g/cm3×20cm3=386g
What does ductility refer to?
Ductility is the ability of a material to bend without breaking.
Compare the space between particles in a solid and a liquid.
In a solid, the space between particles is the least, while in a liquid, the space is more compared to solids.
What is the melting point of the substance?
Refer to Diagram
50°C
What is the difference between a solute and a solvent?
A solute is the substance being dissolved, while a solvent is the medium in which the solute is dissolved.
If a liquid has a density of 1.5 g/cm³, what is its mass if the volume is 100 cm³?
m=D×V=150g.
How is hardness defined in materials?
Hardness is the ability of a solid to resist being scratched.
Describe how intermolecular forces affect the boiling point of a substance.
Stronger intermolecular forces require more energy to overcome, thus leading to a higher boiling point.
You need a lot of heat with some substances to break those forces between molecules
Explain the difference between endothermic and exothermic processes.
Endothermic processes absorb energy (like melting and boiling), while exothermic processes release energy (like freezing and condensation)
Give an example of a physical change.
Water boiling on a stovetop, ripping a piece of paper,etc
What is the density of a substance that has a mass of 200g and a volume of 100cm³?
D=2g/cm3.
Describe the relationship between malleability and gold.
Gold has high malleability because it can be pounded into very thin sheets.
What is the relationship between intermolecular forces and temperature?
As temperature increases, the kinetic energy (movement energy) of particles increases, which can overcome intermolecular forces, leading to phase changes.
Describe the process of condensation on a molecular level.
During condensation, gas particles lose energy and come closer together, forming a liquid.
What is the equation for density?
Density= Mass/Volume
If the density of a substance is 10g/cm³, what would be the volume of 50g of the substance?
V=5cm3.
What does the pH scale indicate about a substance?
The pH scale indicates whether a substance is acidic (pH < 7), neutral (pH = 7), or basic (pH > 7).