Chemistry Test Review- ADV

Front

What is the trend of reactivity of elements on the periodic table?

Back

Reactivity of elements decreases from left to right on the periodic table.

Front

What is true about mixtures made of the same substances?

Back

Both mixtures can be physically separated into their components.

Front

What evidence indicates that new substances have been created in a chemical reaction?

Back

The mixture has different properties than the original substances.

Front

In an atomic model, how many protons, neutrons, and electrons are present in an atom with an atomic number of 7?

Back

7 protons, 7 neutrons, and 7 electrons.

Front

What observation indicates that a gas has formed from mixing two substances?

Back

The mixture has many bubbles.

Front

What is a mixture in chemistry?

Back

A combination of two or more substances that can be physically separated.

Front

What is the difference between a physical change and a chemical change?

Back

A physical change does not alter the chemical composition of a substance, while a chemical change results in the formation of new substances.

Front

What is the significance of the atomic number in an element?

Back

The atomic number indicates the number of protons in an atom and determines the element's identity.

Front

What are the signs of a chemical reaction?

Back

Signs include color change, temperature change, gas production, and formation of a precipitate.

Front

What is the law of conservation of mass?

Back

In a chemical reaction, mass is neither created nor destroyed; it is conserved.