Question

1. explain why there are different branches of chemistry
2. explain why scientists use mass instead of weight for their measurements.
3. summarize why it is important for chemists to study changes in the world at submicroscopic level.
4. infer why chemists use models to study submicroscopic matter.

Explanation:

1. Chemistry is vast. Different branches focus on specific aspects like organic chemistry on carbon - containing compounds, inorganic on non - carbon ones, etc. This specialization helps in in - depth study.
2. Mass is a measure of the amount of matter in an object and is constant. Weight is the force exerted on an object due to gravity and can vary depending on location. Scientists prefer mass for consistency in measurements.
3. Studying changes at the submicroscopic level helps chemists understand the fundamental nature of matter and chemical reactions. It allows prediction and control of chemical behavior.
4. Submicroscopic matter is too small to be directly observed. Models simplify and represent the complex structures and behaviors of submicroscopic particles, making it easier to study and communicate scientific ideas.

Answer:

1. Chemistry is vast and different branches focus on specific aspects for in - depth study.
2. Mass is constant while weight can vary, so mass is preferred for consistent measurements.
3. It helps understand the fundamental nature of matter and reactions, enabling prediction and control.
4. Submicroscopic matter is unobservable directly, and models simplify and represent it for study.