Chemistry: Cation Carries a Positive Charge Practice
Identifying cations, charge, and electron loss
Chemistry: Cation Carries a Positive Charge Practice
Identifying cations, charge, and electron loss
Chemistry - Grade 9-12
- 1
Define a cation in one complete sentence.
A cation is an ion that has a positive charge because it has lost one or more electrons. - 2
A sodium atom loses one electron to form an ion. Write the symbol and charge of the ion that forms.
Losing a negative electron makes the overall charge more positive.
The sodium ion is written as Na+. It has a 1+ charge because the atom lost one negatively charged electron. - 3
Explain why Mg2+ is a cation.
Mg2+ is a cation because it has a positive 2 charge, meaning a magnesium atom lost two electrons. - 4
An ion has 20 protons and 18 electrons. Determine whether the ion is a cation or an anion, and state its charge.
Compare the number of positive protons to the number of negative electrons.
The ion is a cation with a 2+ charge because it has two more protons than electrons. - 5
Write the electron loss equation for the formation of a calcium ion from a neutral calcium atom.
The equation is Ca -> Ca2+ + 2e-. This shows that calcium loses two electrons to form a 2+ cation. - 6
Circle the species that are cations: Cl-, K+, O2-, Fe3+, Ne, Al3+.
Cations are the species with plus signs in their charges.
The cations are K+, Fe3+, and Al3+ because each one has a positive charge. - 7
A diagram shows an atom with 13 protons and 13 electrons. After ion formation, it has 13 protons and 10 electrons. Identify the ion and its charge.
The ion is Al3+. It has a 3+ charge because aluminum has 13 protons and has lost 3 electrons. - 8
Explain why metals commonly form cations rather than anions.
Think about how elements on the left side of the periodic table reach stable electron arrangements.
Metals commonly form cations because they tend to lose valence electrons, giving them more protons than electrons and a positive charge. - 9
A lithium atom forms Li+. How many electrons did the atom lose, and what is the charge on the ion?
The lithium atom lost one electron, and the ion has a 1+ charge. - 10
Complete the table entry in words: Fe2+ has 26 protons and ____ electrons. Explain your answer.
A 2+ charge means there are two fewer electrons than protons.
Fe2+ has 24 electrons. It has a 2+ charge because the neutral iron atom lost 2 electrons while keeping 26 protons. - 11
Compare Na and Na+. Describe one similarity and one difference between them.
Na and Na+ both have 11 protons, so they are both sodium. Na is neutral with 11 electrons, while Na+ has 10 electrons and a positive charge. - 12
An unknown ion X has a charge of 3+. Write a general statement explaining what this charge tells you about its protons and electrons.
Positive charge means the total positive charge is greater than the total negative charge.
A 3+ charge means the ion has three more protons than electrons. It formed when a neutral atom lost three electrons.