What is the mass number of this element?
[tex] { }_{14}^{29} Si [/tex]
A. 29
B. 43
C. 14
D. 15
Answer (2)
Recognize that in the notation Z A X , A represents the mass number.
Identify the mass number in the given element 14 29 S i as 29 .
State the final answer as 29 .
Explanation
Understanding the Notation The problem asks us to identify the mass number of the element Silicon (Si) represented as 14 29 S i . In this notation, the number at the bottom left (14) is the atomic number, and the number at the top left (29) is the mass number.
Identifying the Mass Number The mass number is the total number of protons and neutrons in the nucleus of an atom. In the given notation 14 29 S i , the mass number is explicitly given as 29.
Final Answer Therefore, the mass number of the element 14 29 S i is 29 .
Examples
In nuclear chemistry, knowing the mass number of an isotope is crucial for understanding its stability and radioactive properties. For example, carbon-14 ( 14 C ) is used in radiocarbon dating to determine the age of organic materials. The mass number (14 in this case) helps scientists differentiate it from the more common carbon-12 ( 12 C ). This distinction is vital in various applications, from archaeology to environmental science, where the isotopic composition provides valuable information.
The mass number of the element 14 29 Si is 29, as indicated by the top left number in the notation. This number represents the total number of protons and neutrons in the nucleus.
;
