Question

short answer questions

1. explain how the periodic table is organized and how you can identify elements with similar properties. your response:
2. describe the difference between a pure substance and a mixture. provide an example of each. your response:
3. explain how the density of an object is related to its mass and volume. why is this property important in identifying substances? your response:
4. describe the difference between acids, bases, and salts. provide an example of each. your response:

reflection

1. reflect on what you found most challenging in this unit and why. how did you overcome these challenges? your response:

Explanation:

7.

The periodic table organizes elements by atomic number (number of protons). Elements are arranged in periods (rows) and groups (columns). Elements in the same group have similar properties because they have the same number of valence electrons. For example, the alkali - metals in Group 1 all have 1 valence electron and are highly reactive.

A pure substance is made up of only one type of particle (atom or molecule), like gold (Au) which is made of only gold atoms. A mixture contains two or more different substances physically combined, such as a salad with different vegetables.

Density ($
ho$) is defined as mass ($m$) divided by volume ($V$), $
ho=\frac{m}{V}$. It is important for identifying substances because each pure substance has a characteristic density at a given temperature and pressure. For example, lead is denser than aluminum.

Answer:

The periodic table arranges elements by increasing atomic number. Elements in the same group have similar properties due to the same number of valence electrons.

8.