Which safety precaution is essential to prevent chemical exposure in the laboratory?

• Wearing gloves and safety goggles at all times.

• Tasting small amounts of chemicals to identify them.

• Ignoring spills if they seem minor.

• Leaving the laboratory without cleaning up.

Among laboratory tools, which is the most precise for measuring liquid volume to the nearest milliliter?

• Beaker

• Volumetric flask

• Graduated cylinder

• Pipette

What distinguishes a local scientist’s contributions compared to a foreign scientist’s in terms of relevance to community issues?

• Local scientists only work on global problems.

• Local scientists focus on research affecting their own region.

• Foreign scientists do not conduct experiments.

• Local scientists focus only on theoretical work.

Which statement best defines a hypothesis?

• A guess with no evidence.

• A testable prediction based on observation and prior knowledge.

• A final conclusion after an experiment.

• A detailed explanation of experimental results.

In an experiment testing plant growth under different light colors, what is the independent variable?

• Amount of water supplied.

• Color of the light.

• Height of the plants.

• Type of soil used.

After collecting data in an experiment, what logical process is used to interpret the results?

• Analyzing data using graphs, tables, or statistics to identify patterns.

• Formulating new hypotheses without data analysis.

• Ignoring unexpected data points.

• Repeating the experiment without explanation.

Which step in the scientific method helps ensure that investigations can be verified by others?

• Forming an unsupported hypothesis.

• Drawing conclusions based on personal belief.

• Detailed recording of procedures and results.

• Keeping experiment methods secret.

What key characteristic of molecules in solids explains their definite shape and volume?

• Molecules move rapidly and randomly.

• Molecules are spread far apart.

• Molecules are tightly packed and vibrate in fixed positions.

• Molecules flow freely past each other.

Which statement correctly describes the movement of water molecules during boiling?

• Water molecules slow down and form a solid.

• Water molecules gain energy, move rapidly, and change into gas.

• Water molecules lose energy and settle at the bottom.

• Water molecules remain fixed in place.

How do atoms combine to form molecules?

• By forming chemical bonds between atoms.

• By mixing physically without bonding.

• By separating into ions.

• By existing independently only.