Clear, accurate chemistry definitions 1,517 terms 6 topics 118-element periodic table
General Chemistry

Daughter Nuclide

Definition and meaning of Daughter Nuclide in chemistry.

A daughter nuclide is the new atom left behind after a radioactive element decays. When an unstable parent nucleus spits out radiation, it changes its basic identity. The newly formed atom is officially called the daughter nuclide by nuclear chemists.

In more detail

Radioactive atoms have too much internal energy or a bad mix of protons and neutrons. To find stability, the heavy parent nucleus breaks apart and releases small particles. This physical loss of pieces transforms the original element into a brand new element.

Different types of radioactive decay create different types of daughter nuclides. Alpha decay throws away two protons and two neutrons in a single chunk. This drops the new atom's mass by four and its atomic number by two.

Beta decay turns a neutron into a proton and shoots out an electron. This keeps the mass the same but increases the atomic number by one. Chemists find the daughter nuclide by balancing the numbers in a nuclear equation.

The total mass and total charge must stay exactly the same on both sides. Sometimes a daughter nuclide is completely stable and will never change again. Other times, the daughter is also radioactive and must undergo its own decay. This creates a long chain of transforming atoms known as a decay series.

Key facts

FieldGeneral Chemistry
OriginCreated when a parent nuclide undergoes radioactive decay
Mass BalanceThe total mass number stays constant during the decay process
Charge BalanceThe total atomic number stays constant during the decay process
Long Term StabilityMay be completely stable or highly radioactive
Decay SeriesA chain where daughters act as parents for future decays
Example

Uranium-238 is a heavy parent nuclide found naturally inside rocks in the ground. Its nucleus is too large to stay together forever without eventually breaking apart. It undergoes alpha decay by spitting out a small chunk of two protons and two neutrons. The original uranium atom loses two protons, so it becomes the element thorium. The starting mass of 238 drops by four units to become exactly 234. Therefore, the new daughter nuclide is specifically identified as the isotope thorium-234. Thorium-234 is also radioactive and will eventually become a parent to another daughter. This continuous chain reaction stops only when a completely stable lead atom forms.

Frequently asked questions

Is a daughter nuclide always a stable chemical element?

No. Many daughter nuclides are highly radioactive and will quickly decay into yet another new element.

How do chemists predict the exact identity of a daughter nuclide?

They balance the math in a nuclear equation so the total mass and total protons remain equal.

What happens to a daughter nuclide if it is also radioactive?

It simply becomes a parent nuclide itself and undergoes a new decay event to find stability.

Related terms