counting atoms and conservation mass

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

What happens to mass during a chemical reaction in an open container?

Back

In an open container, some mass may be lost as gases escape, leading to a decrease in the measured mass of the sample.

Front

How do you determine the number of atoms in a chemical formula?

Back

Count the subscripts in the formula; if there is no subscript, it is understood to be 1.

Front

What is the molecular formula for glucose?

Back

C₆H₁₂O₆.

Front

How many oxygen atoms are in the sulfate ion (SO₄²⁻)?

Back

There are 4 oxygen atoms in the sulfate ion.

Front

What is the significance of subscripts in chemical formulas?

Back

Subscripts indicate the number of atoms of each element in a molecule.

Front

How many total atoms are in Al₂(SO₄)₃?

Back

There are 14 total atoms: 2 Al, 3 S, and 12 O.

Front

What is the total number of hydrogen atoms in Al(OH)₃?

Back

There are 3 hydrogen atoms in Al(OH)₃.

Front

What is a chemical reaction?

Back

A chemical reaction is a process that leads to the transformation of one set of chemical substances to another.

Front

What is the role of heat in a chemical reaction?

Back

Heat can provide energy to break bonds in reactants, facilitating the reaction.