Question

total recall

1. what are the common physical states of matter?
2. how do the particle models for the states of matter differ?
3. what is the difference between an endothermic reaction and an exothermic reaction?
4. in what ways do the three fundamental states of matter differ?

Explanation:

1. The common physical states of matter are solid, liquid, and gas. Solids have a definite shape and volume, liquids have a definite volume but take the shape of their container, and gases have neither a definite shape nor volume.
2. In the particle - model, solid particles are closely packed and vibrate in fixed positions, liquid particles are close but can move past each other, and gas particles are far apart and move freely.
3. An endothermic reaction absorbs heat from the surroundings (temperature of surroundings decreases), while an exothermic reaction releases heat to the surroundings (temperature of surroundings increases).
4. Solids have high density and low compressibility, liquids have moderate density and low compressibility, and gases have low density and high compressibility. Also, their particle arrangements and movement characteristics differ as described above.

Answer:

1. Solid, liquid, gas
2. Solid particles are closely - packed and vibrate in place; liquid particles are close and can move past each other; gas particles are far apart and move freely.
3. Endothermic reactions absorb heat, exothermic reactions release heat.
4. Density, compressibility, particle arrangement and movement characteristics differ.