Atoms and the Periodic Table

Which of these statements should be included to explain what was missing from Dalton’s atomic theory?

• . Atoms are made up of smaller particles

• . All atoms of the same element are identical.

• Atoms of different elements have different masses.

• Compounds form when atoms of different elements combine in a specific ratio.

What incorrect idea in Bohr’s understanding of the atom was replaced in later theories?

• Atoms cannot be divided.

• An atom is mostly empty space.

• In an atom, electrons orbit the nucleus like planets orbit the sun.

• An atom includes electrons embedded in a sphere of positive charge.

New theories usually don’t start “from scratch.” For example, the modern model of the atom is the result of new information added to the cloud model. What is the main difference between the cloud model of the atom and the modern model?

• Only the modern model includes protons.

• The cloud model does not include neutrons.

• Electrons move in specific orbits in the cloud model.

• Electrons exist in a cloud around the nucleus in the modern model

Which of these statements should be included about Democritus' atomic theory?

• All atoms of a given element are identical in mass and properties.

• All atoms are uncut table, meaning not able to divide

• Electrons move only in specific (orbits) around an atom's nucleus

• Electrons move rapidly within (a cloud-like) region

Which particles do not affect the charge of the atom?

• protons

• .neutrons

• electrons

Atoms with the same number of protons and different numbers of neutrons are:

• Atomic number

• Atomic mass

• isotopes

According to the cloud model, electrons move in specific orbits like planets do

• True

• False

. What is this model?

• cloud model

• Bohr's model

• Rather Ford model

• Thomson model

• Dalton model

represents the area around an atom's nucleus where electrons are most likely to be found. It is a sphere that surrounds the microscopic nucleus, although it is often rendered as a ring in two-dimensional pictures

• cloud model

• Bohr's model

• Rather Ford model

• Thomson model

• Dalton model

. What is this model?

• cloud model

• Bohr's model

• Rather Ford model

• Thomson model

• Dalton model