MSPS1-1 Structure of Atoms

Use the model shown below to answer the following question. What is the mass number of the atom? (8.5A)

• 6

• 11

• 16

• 10

Answer explanation

The mass number of an atom is the total number of protons and neutrons in its nucleus. In this case, the model indicates there are 11 nucleons, making the mass number 11, which corresponds to the correct answer.

Tags

NGSS.MS-PS1-1

If an atom has a mass of 6 and contains 3 electrons, its atomic number must be?

• 6

• 3

• 18

• 12

Answer explanation

The atomic number of an atom is defined by the number of protons it has. Since the atom has 3 electrons, it must also have 3 protons to maintain electrical neutrality. Therefore, its atomic number is 3.

Tags

NGSS.MS-PS1-1

What are the three main parts of an atom?

• Protons, Neutrons, and Electrons

• Protons, Neutrons, and Photons

• Electrons, Neutrons, and Photons

• Protons, Electrons, and Photons

Answer explanation

The three main parts of an atom are protons, neutrons, and electrons. Protons and neutrons are found in the nucleus, while electrons orbit around the nucleus, making the first answer choice correct.

Tags

NGSS.MS-PS1-1

Which part of the atom has a positive charge?

• Neutron

• Electron

• Proton

• Nucleus

Answer explanation

The proton is the part of the atom that carries a positive charge. Neutrons are neutral, electrons have a negative charge, and the nucleus contains protons and neutrons.

Where are electrons located in an atom?

• In the nucleus

• Orbiting the nucleus

• In the proton cloud

• In the neutron cloud

Answer explanation

Electrons are located in regions around the nucleus called orbitals, where they move in various paths. This is why the correct answer is 'Orbiting the nucleus', as they do not reside in the nucleus or any 'cloud'.

What is the atomic number of an element?

• The number of protons in the nucleus

• The number of neutrons in the nucleus

• The number of electrons in the atom

• The total number of protons and neutrons

Answer explanation

The atomic number of an element is defined as the number of protons in its nucleus. This number determines the element's identity and its position in the periodic table.

What does the mass number of an atom represent?

• The number of protons

• The number of electrons

• The number of neutrons

• The total number of protons and neutrons

Answer explanation

The mass number of an atom is the sum of protons and neutrons in its nucleus. It does not represent the number of electrons or just neutrons, making 'the total number of protons and neutrons' the correct choice.

If an atom has 6 protons, 6 neutrons, and 6 electrons, what is its atomic number?

• 6

• 12

• 18

• 0

Answer explanation

The atomic number of an atom is defined by the number of protons it has. Since this atom has 6 protons, its atomic number is 6, making the correct answer 6.

Tags

NGSS.MS-PS1-1

If an atom has 8 protons and 8 neutrons, what is its mass number?

• 8

• 16

• 24

• 32

Answer explanation

The mass number of an atom is the sum of its protons and neutrons. Here, 8 protons + 8 neutrons = 16. Therefore, the mass number is 16.

Which part of the atom is neutral, having no charge?

• Proton

• Electron

• Neutron

• Nucleus

Answer explanation

The neutron is the part of the atom that is neutral, meaning it has no charge. In contrast, protons are positively charged and electrons are negatively charged.