Textbook Question
Consider the following atoms in which X represents the chemical symbol of the element: (4.4, 4.5) ¹⁶₈X ¹⁶₉X ¹⁸₁₀X ¹⁷₈X ¹⁸₈Xa. What atoms have the same number of protons?
1199
views
4. Atoms and Elements
Isotopes
Struggling with Introduction to Chemistry?
Join thousands of students who trust us to help them ace their exams!Watch the first videoMultiple Choice
An atom has 3 protons and 4 neutrons. Which isotope is it?
A
Helium-7 ()
B
Lithium-6 ()
C
Lithium-7 ()
D
Beryllium-7 ()
Verified step by step guidance1
Identify the number of protons in the atom, which determines the element. Here, the atom has 3 protons.
Recall that the atomic number (number of protons) corresponds to a specific element on the periodic table. For example, 3 protons correspond to the element Lithium (Li).
Calculate the mass number of the isotope by adding the number of protons and neutrons: \(\text{mass number} = \text{protons} + \text{neutrons}\).
Substitute the given values: \(\text{mass number} = 3 + 4\).
Combine the element symbol with the mass number to name the isotope, written as \(\mathrm{^{mass\ number}Element}\), which in this case is \(\mathrm{^{7}Li}\).
Related Videos
Related Practice
