A liquid has a mass of 500 g and occupies a volume of 250 cm³. Calculate the density of the liquid (Density of materials) (Density of materials; particle reasoning focus: Calculate mass when density and volume are known) (Density of materials; definition focus: Calculate mass when density and volume are known) ? P43-002 Density of materials checkpoint

The density of the liquid is 2 g/cm³. In P43-002, the answer must mention density, mass, volume and connect it to Density of materials.

Definition lens: Give the precise definition, then add a context sentence that shows how it is used. This question asks: A liquid has a mass of 500 g and occupies a volume of 250 cm³. Calculate the density of the liquid (Density of materials) (Density of materials; particle reasoning focus: Calculate mass when density and volume are known) (Density of materials; definition focus: Calculate mass when density and volume are known) ?. The correct response is The density of the liquid is 2 g/cm³. In P43-002, the answer must mention density, mass, volume and connect it to Density of materials., because density links mass and volume, so the answer must preserve which quantity is being calculated. In Density of materials, the marking point should connect directly to calculate mass when density and volume are known. If the question includes values, the working must keep the appropriate unit and operation; if it is an explanation, it must name the relevant particle behaviour or energy change. This item belongs to Changes of state and the particle model, so avoid answers that switch to a different quantity, confuse heat with temperature, or describe gas pressure without collisions when collisions are the reason. Checkpoint 30 is distinct because it uses this exact question context and the definition lens rather than a generic particle-model sentence.