Strontium Atoms and Ions Concepts

This video tutorial explains how to determine the number of protons and electrons in the strontium ion (Sr2+). It begins by identifying the atomic number of strontium from the periodic table, which is 38, indicating 38 protons. The video then discusses the difference between neutral atoms and ions, focusing on the change in electron count. For Sr2+, the loss of two electrons results in 36 electrons, creating a positive charge. The tutorial concludes with a reference to additional resources for learning about strontium isotopes.

What is the first step in determining the number of protons and electrons in the Sr2+ ion?

• Count the number of neutrons.

• Look at the periodic table for the atomic number.

• Measure the ion's charge.

• Check the atomic mass of strontium.

What does the atomic number of an element represent?

• The total number of electrons in a neutral atom.

• The number of neutrons in the nucleus.

• The number of protons in the nucleus.

• The mass of the atom.

How many protons does a neutral strontium atom have?

• 38

• 42

• 36

• 40

What is the main difference between a neutral atom and an ion?

• The atomic number changes.

• The number of neutrons changes.

• The number of protons changes.

• The number of electrons changes.

How many electrons does a neutral strontium atom have?

• 40

• 42

• 38

• 36

What does the '2+' in Sr2+ indicate?

• The ion has lost two protons.

• The ion has gained two neutrons.

• The ion has lost two electrons.

• The ion has gained two protons.

How many electrons are present in the Sr2+ ion?

• 38

• 36

• 34

• 40

Where can you find more information about the isotopes of strontium?

• In the video description link.

• In the video comments section.

• In the periodic table.

• In the textbook appendix.