238/92 U → 4/2 He + 234/90 blank
The element in the missing box is ____. (Use the symbol from the periodic table, not the whole name.)
Th
To determine the missing element, we need to understand the given nuclear equation:
238/92 U → 4/2 He + 234/90 X
In this equation, the initial element (Uranium-238) undergoes alpha decay, producing an alpha particle (Helium-4) and an unknown element (X).
To determine the missing element, we need to find the element with atomic number 90. Referring to the periodic table, we can identify that the element with atomic number 90 is Thorium (Th).
Therefore, the missing element, represented by the symbol from the periodic table, is 90 Th.
To solve this question, we can use the conservation of mass and charge in a nuclear reaction. The total mass number and atomic number need to be equal on both sides of the equation.
Given:
238/92 U → 4/2 He + 234/90 blank
We can start by analyzing the mass number (the top number) on both sides of the equation. On the left side, uranium (U) has a mass number of 238, and on the right side, helium (He) has a mass number of 4.
238 = 4 + mass number of blank
Simplifying the equation, we have:
mass number of blank = 238 - 4
mass number of blank = 234
Next, let's consider the atomic number (the bottom number) on both sides of the equation. Uranium (U) has an atomic number of 92, and helium (He) has an atomic number of 2.
92 = 2 + atomic number of blank
Simplifying the equation, we have:
atomic number of blank = 92 - 2
atomic number of blank = 90
Now, using the periodic table, we can find the element with an atomic number of 90. The element with an atomic number of 90 is thorium, which is represented by the symbol Th.
Therefore, the element in the missing box is Th.