Semester Exam Rev

Front

What is a physical change?

Back

A physical change is a change that affects one or more physical properties of a substance without altering its chemical composition.

Front

What evidence indicates a physical change has occurred?

Back

Changes in color, state, or temperature can indicate a physical change, such as a solid dissolving in a liquid.

Front

What is the difference between speed and velocity?

Back

Speed is a scalar quantity that refers to how fast an object is moving, while velocity is a vector quantity that includes both speed and direction.

Front

What does it mean for forces to be balanced?

Back

Balanced forces occur when two forces acting on an object are equal in size but opposite in direction, resulting in no change in motion.

Front

What are unbalanced forces?

Back

Unbalanced forces occur when two forces acting on an object are not equal, causing the object to accelerate in the direction of the greater force.

Front

How do you determine the number of atoms in a molecule?

Back

To find the total number of atoms in a molecule, add the number of each type of atom present in the chemical formula.

Front

What is serotonin and its role in the human body?

Back

Serotonin is a neurotransmitter that helps relay messages in the brain, influencing mood, sleep, and other functions.

Front

What is the formula for ammonium chromate?

Back

The formula for ammonium chromate is (NH₄)₂CrO₄.

Front

How many nitrogen atoms are in (NH₄)₂CrO₄?

Back

There are 2 nitrogen atoms in (NH₄)₂CrO₄.

Front

What is the significance of temperature in physical changes?

Back

Temperature can indicate whether a physical change has occurred, as it may change when a substance changes state or dissolves.