A metal block has a mass of 300 g and a volume of 100 cm³. What is its density (Density of materials)

The correct answer is 3 g/cm³.

Graph lens: Read the trend, flat section, gradient, or axis labels before explaining the physical meaning. This question asks: A metal block has a mass of 300 g and a volume of 100 cm³. What is its density (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 27 is distinct because it uses this exact question context and the graph lens rather than a generic particle-model sentence.