A metal cube has a mass of 300 grams and a volume of 100 cm³. Calculate the density of the metal (Density of materials)

3 g/cm³

Unit lens: Check the units before giving the final statement so the physics quantity is not swapped. This question asks: A metal cube has a mass of 300 grams and a volume of 100 cm³. Calculate the density of the metal (Density of materials). The correct response is 3 g/cm³, 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 density when mass 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 25 is distinct because it uses this exact question context and the unit lens rather than a generic particle-model sentence.