Final answer:
If it's not safe to determine a certain physical property of a substance, the student should (d) refrain from determining the property and seek assistance or use appropriate equipment following laboratory safety protocols.
Step-by-step explanation:
When it's not safe to determine a certain physical property of a substance, one should always choose safety first. Refraining from determining the property is the most responsible course of action. If you are in doubt, the steps to take could include using appropriate equipment, seeking assistance from a knowledgeable individual such as your teacher, or choosing not to perform the determination at all. In a school setting, student safety is paramount, so it is essential to follow all safety protocols, such as never eating or drinking in the lab, ensuring that materials like test tubes and beakers are completely cleaned, and being vigilant when using flames or heat sources. If anything out of the ordinary occurs, notify the teacher immediately.
When determining a substance's identity or its properties, a chemist might measure various physical and chemical properties. Physical properties can include density, melting point, or solubility, whereas chemical properties include reactivity with other chemicals or changes to the substance's composition under certain conditions. In the lab, correctly identifying and measuring these properties often involves sophisticated techniques and adherence to strict safety measures.