Before Ella combines substances to create a specific material, she needs to know the physical and chemical properties of the substances and how they react chemically. This knowledge is crucial for understanding how the substances will interact, whether they will react in a desirable way, and what the new material will be like in terms of its properties and stability.
Additionally, knowing whether the substances are synthetic or from natural resources might provide context for their properties and potential applications, but the most critical information directly affecting the success of her material creation is the behavior and characteristics of the substances she plans to combine.