an oxygen atom with 10 neutrons Express your answer as an isotope
an isotope with four protons and five neutrons
Express your answer as an isotope.
an isotope with 25 electrons and 28 neutrons
Express your answer as an isotope.
The Correct Answer and Explanation is :
To express the isotopes as requested, let’s go through each one step by step:
1. Oxygen atom with 10 neutrons:
An oxygen atom normally has 8 protons because the atomic number of oxygen is 8. The number of neutrons in an isotope can vary, so this one has 10 neutrons.
To express this oxygen isotope, we use the following format: Isotope notation=Element symbol (Mass number)\text{Isotope notation} = \text{Element symbol} \, (\text{Mass number})
The mass number is the sum of the protons and neutrons, so in this case: 8(protons)+10(neutrons)=188 (\text{protons}) + 10 (\text{neutrons}) = 18
Therefore, the isotope is: \text{Oxygen-18} \quad \text{or} \quad ^{18}O
This isotope of oxygen is often referred to as oxygen-18.
2. Isotope with 4 protons and 5 neutrons:
The number of protons determines the element. In this case, the atom has 4 protons, which means it is helium (since the atomic number of helium is 4). The atom also has 5 neutrons.
To express this isotope, calculate the mass number: 4(protons)+5(neutrons)=94 (\text{protons}) + 5 (\text{neutrons}) = 9
The isotope is: \text{Helium-9} \quad \text{or} \quad ^{9}He
This is a rare isotope of helium, as most helium atoms are helium-4.
3. Isotope with 25 electrons and 28 neutrons:
In a neutral atom, the number of electrons equals the number of protons. Since this atom has 25 electrons, it must have 25 protons, making it manganese (because the atomic number of manganese is 25). The atom also has 28 neutrons.
To express this isotope, calculate the mass number: 25(protons)+28(neutrons)=5325 (\text{protons}) + 28 (\text{neutrons}) = 53
The isotope is: \text{Manganese-53} \quad \text{or} \quad ^{53}Mn
Explanation:
Isotopes are versions of elements that differ in the number of neutrons, while the number of protons remains constant. The number of protons in an atom defines which element it is, and the total number of protons and neutrons gives the atom’s mass number. For example, oxygen-18 is an isotope of oxygen because it has 8 protons (defining it as oxygen) and 10 neutrons. Similarly, the isotope helium-9 differs from the more common helium-4 in its neutron count. Isotopes of the same element often have similar chemical properties but may differ in physical properties, such as mass or radioactivity. For example, manganese-53 is a stable isotope of manganese, which has 25 protons and 28 neutrons.