Question

ne fais pas de calculs. (a) lequel est plus lourd: 1 g dor ou 1 g daluminium? expliquer.

Explanation:

The unit "gram (g)" is a unit of mass (and in the context of weight on Earth, mass is often used interchangeably with weight in everyday language). If both substances have a mass of 1 gram, their weights (the force due to gravity acting on them) are equal because weight $W = mg$ (where $m$ is mass and $g$ is the acceleration due to gravity), and since $m = 1\space g$ is the same for both and $g$ is constant near the Earth's surface, their weights are equal. However, if we consider density (which relates to how much mass is in a given volume), gold is denser than aluminium, meaning 1 gram of gold would occupy a much smaller volume than 1 gram of aluminium, but the question is about which is "plus lourd" (heavier) in terms of the amount of mass (or weight), and since both have 1 gram of mass, they are equally heavy.

Answer:

1 g of gold and 1 g of aluminium have the same weight.