Elements, Compounds, and Mixtures/Balancing Equations

Front

What is the definition of a mixture?

Back

A mixture is a combination of two or more substances that are not chemically bonded and can be separated by physical means.

Front

What distinguishes a compound from a mixture?

Back

A compound is a substance formed when two or more elements are chemically bonded together, while a mixture consists of two or more substances that are not chemically bonded.

Front

What is the law of conservation of mass?

Back

The law of conservation of mass states that mass is neither created nor destroyed in a chemical reaction; the total mass of reactants equals the total mass of products.

Front

How do you determine if a chemical equation is balanced?

Back

A chemical equation is balanced when the number of atoms of each element is the same on both sides of the equation.

Front

What is the weight of an ice cube after it melts?

Back

The weight of the ice cube remains the same after it melts; it will still weigh 20 grams.

Front

In a chemical reaction, if reactant A has 5g and product C has 9g, how do you find the weight of reactant B?

Back

To find the weight of reactant B, use the law of conservation of mass: weight of A + weight of B = weight of C. Therefore, B = C - A = 9g - 5g = 4g.

Front

What is an example of a homogeneous mixture?

Back

An example of a homogeneous mixture is saltwater, where the salt is completely dissolved in water.

Front

What is an example of a heterogeneous mixture?

Back

An example of a heterogeneous mixture is a salad, where the different ingredients can be seen and separated.

Front

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

Back

A physical change alters the form of a substance but not its chemical composition, while a chemical change results in the formation of new substances.

Front

What is a chemical equation?

Back

A chemical equation is a symbolic representation of a chemical reaction, showing the reactants and products along with their quantities.