Unit 1 Test K Review

Front

What is a chemical change?

Back

A chemical change occurs when a substance transforms into a different substance, often involving the release of gas, change in color, or formation of a precipitate.

Front

What happens during thermal equilibrium?

Back

Thermal equilibrium is reached when heat flows between objects until all particles are at the same temperature.

Front

How do you calculate the number of moles from atoms?

Back

To find the number of moles from atoms, use the formula: Moles = Number of atoms / Avogadro's number (6.022 x 10^23).

Front

What does the Law of Conservation of Mass state?

Back

The Law of Conservation of Mass states that mass is neither created nor destroyed in a chemical reaction; it is conserved.

Front

How do you read a graduated cylinder?

Back

To read a graduated cylinder, look at the bottom of the meniscus at eye level and include one digit of uncertainty.

Front

What is the definition of a mole in chemistry?

Back

A mole is a unit that measures the amount of substance, defined as containing exactly 6.022 x 10^23 particles (atoms, molecules, etc.).

Front

What is an example of a physical change?

Back

An example of a physical change is ice melting into water, where the substance changes state but not its chemical composition.

Front

What is the difference between an endothermic and exothermic reaction?

Back

An endothermic reaction absorbs heat from the surroundings, while an exothermic reaction releases heat.

Front

What is the significance of the digit of uncertainty in measurements?

Back

The digit of uncertainty indicates the precision of a measurement, reflecting the estimated error in the reading.

Front

What is kinetic energy?

Back

Kinetic energy is the energy of an object due to its motion, calculated using the formula: KE = 1/2 mv^2, where m is mass and v is velocity.