Review Quiz! Elements!

What did Mendeleev discover?

• The periodic table.

• All of the elements

• A set of patterns that applied to all of the elements.

• The planet Mercury.

Answer explanation

Mendeleev is best known for his discovery of the periodic law and the creation of the first periodic table of elements. He noticed that when the elements were arranged in order of increasing atomic mass, certain elements had similar chemical properties. He used this observation to create the periodic table, which organizes elements into groups based on their chemical properties. This discovery revolutionized the field of chemistry and is still used today.

What is an element?

• Earth, Air, Fire, Water.

• a pure substance that cannot be broken down into other substances.

• 2 atoms bound together.

• A reaction in nature.

Answer explanation

An element is a substance that cannot be broken down into simpler substances by chemical means. Elements are the basic building blocks of all matter and are composed of only one type of atom. There are 118 known elements, each with its own unique atomic number, atomic mass, and chemical properties.

When Mendeleev organized his periodic table and noticed patterns, what was he arranging it by?

• color

• weight

• size

• atomic mass

Answer explanation

Mendeleev organized his periodic table by arranging the elements in order of increasing atomic mass. He noticed that when the elements were arranged in this way, certain elements with similar properties appeared in the same column. This allowed him to group elements into families and identify patterns in their properties.

The first periodic table was published by Mendeleev in what year?

• 1972

• 2023

• 3025

• 1869

Answer explanation

The first periodic table was published by Russian chemist Dmitri Mendeleev in 1869.

Please find the electrons!

Answer explanation

Electrons are the negatively charged particles that make up the atom. They are found in the electron cloud, which is the region around the nucleus of an atom where the electrons are located. Electrons are constantly in motion and can be found in different energy levels.

Tags

NGSS.MS-PS1-1

Find the protons!

Answer explanation

Protons are positively charged particles found in the nucleus of an atom. They are one of the three main subatomic particles, along with neutrons and electrons. Protons have a mass of 1.67 x 10-27 kg and a charge of +1. They are the building blocks of all matter and are responsible for the chemical properties of atoms.

Tags

NGSS.MS-PS1-1

Label the diagram!

b

a

c

d

Atomic number

Atomic mass

Element name.

Chemical symbol

How is the periodic table useful?

• It can give you instruction on how to make things.

• It can tell you how long chemical reactions take.

• It is only useful to people selling periodic tables.

• An element's properties can be predicted from its place on the periodic table.

Answer explanation

The periodic table is a useful tool for organizing and understanding the chemical elements. It arranges the elements in order of increasing atomic number, which is the number of protons in the nucleus of an atom. This arrangement allows for easy comparison of elements and their properties, such as atomic mass, electronegativity, and reactivity. It also helps to predict the properties of elements that have not yet been discovered. The periodic table is an invaluable tool for chemists, physicists, and other scientists.

What is a period of the periodic table?

• It is the rows on the table.

• It is the columns on the table.

• It is one of the boxes on the table.

• It is the last two columns.

Answer explanation

A period of the periodic table is a row of elements. Each period contains elements with similar properties, as elements in the same period have the same number of electron shells. The elements in a period are arranged in order of increasing atomic number.

What are the groups on the periodic table.

• The rows of the table.

• The columns of the table.

• The diagonal line of metalloids.