sp14 kinetic theory + states of matter Flashcards
Define Kinetic Theory in relation to matter.
Kinetic Theory explains matter as being composed of tiny particles in constant motion, with behaviours of matter attributed to the movement and forces between these particles.
How do changes of state differ from chemical reactions in terms of particle behaviour?
Changes of state involve physical changes where particles rearrange without forming new substances, unlike chemical reactions that create new substances.
Do particles in a solid state have high or low kinetic energy?
Particles in a solid state have low kinetic energy, allowing them to vibrate in fixed positions due to strong forces of attraction.
Describe the behaviour of particles in a liquid state compared to a solid state.
In a liquid state, particles have weaker forces of attraction, enabling them to move past each other and form irregular arrangements, unlike the fixed positions in a solid state.
Define change of state in terms of particle arrangement.
A change of state involves a rearrangement of particles due to differences in energy levels.
Do particles in a gas have high or low kinetic energy?
Particles in a gas have high kinetic energy and move in random directions at high speeds.
Describe the role of thermal energy in a substance.
Thermal energy in a substance is held by particles in their kinetic energy stores, representing the total internal energy of the substance.
Describe the relationship between mass and state changes of a substance
The mass of a substance remains constant when it changes state as the particles are only being rearranged
Define density and how it is affected by changes in state of a substance.
Density is the mass of a substance per unit volume. As a substance changes state, its density changes due to the variation in volume.
How does the density of a substance typically vary as it changes from solid to liquid to gas?
Substances are most dense in their solid state and least dense in their gaseous state, with density decreasing as the substance changes from solid to liquid to gas.
Describe the concept of density in relation to the spaces between particles in a substance.
Density is determined by the mass of particles in a substance, not the spaces between them. As a substance expands or contracts, its volume changes while its mass remains constant.
