An electric device delivers a current of [tex]$15.0 A$[/tex] for 30 seconds. How many electrons flow through it?
Answer (2)
Conserve the mass number: 16 + 20 = 12 + A , which gives A = 24 .
Conserve the atomic number: 8 + 10 = 6 + Z , which gives Z = 12 .
Identify the element with atomic number 12 as Magnesium (Mg).
The missing element is 12 24 M g , so the answer is Magnesium.
Explanation
Understanding the Problem We are given a nuclear reaction and asked to find the missing element. In a nuclear reaction, both the total mass number (superscript) and the total atomic number (subscript) must be conserved on both sides of the equation. The given reaction is:
8 16 O + 10 20 N e → 6 12 C + ?
Let's denote the missing element as Z A X , where A is the mass number and Z is the atomic number.
Conserving Mass Number To find the mass number A , we use the conservation of mass number:
16 + 20 = 12 + A
36 = 12 + A
A = 36 − 12
A = 24
Conserving Atomic Number To find the atomic number Z , we use the conservation of atomic number:
8 + 10 = 6 + Z
18 = 6 + Z
Z = 18 − 6
Z = 12
Identifying the Element Now we know that the missing element has a mass number of 24 and an atomic number of 12. The element with atomic number 12 is Magnesium (Mg). Therefore, the missing element is 12 24 M g .
Final Answer The missing element in the nuclear reaction is Magnesium ( 12 24 M g ).
Examples
Nuclear reactions are used in various applications, such as nuclear medicine for diagnostics and treatment, and in nuclear power plants to generate electricity. Understanding nuclear reactions helps scientists develop new technologies and improve existing ones. For example, the production of medical isotopes relies on controlled nuclear reactions to create specific radioactive materials that can be used to diagnose diseases or treat cancer. Similarly, nuclear power plants use nuclear fission reactions to generate heat, which is then used to produce steam and drive turbines to generate electricity. The principles of nuclear reactions are also crucial in astrophysics, where they explain the energy production in stars and the synthesis of elements in the universe.
Approximately 2.81 x 10^21 electrons flow through an electric device delivering a current of 15.0 A for 30 seconds. This is calculated using the formula Q = I x t to find the charge, and then dividing by the charge of a single electron. This calculation helps understand the relationship between current, charge, and time in electric circuits.
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