Open 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?
4. Atoms and Elements
Isotopes
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Join thousands of students who trust us to help them ace their exams!Watch the first videoMultiple Choice
Which of the following answers give the correct number of subatomic particles for 
?
A
38 protons, 38 neutrons and 38 electrons
B
88 protons, 50 neutrons and 50 electrons
C
38 protons, 50 neutrons and 38 electrons
D
38 protons, 27 neutrons and 13 electrons
Verified step by step guidance1
Identify the element from the symbol 'Sr'. 'Sr' stands for Strontium.
Determine the atomic number of Strontium, which is given as 38. This number represents the number of protons in the nucleus of the atom.
The atomic number also indicates the number of electrons in a neutral atom. Therefore, Strontium has 38 electrons.
The number above the element symbol is the mass number, which is 88 in this case. The mass number is the sum of protons and neutrons in the nucleus.
Calculate the number of neutrons by subtracting the atomic number from the mass number: 88 (mass number) - 38 (atomic number) = 50 neutrons.
