What would the nuclear equation be for the beta-decay of strontium-90?
Here's what I got.
A beta particle,
At the same time, a
Now, because a neutron is being converted into a proton, the mass number of the nuclide will not change. However, its atomic number, which tells you how many protons are present inside the nuclues, will change.
This means that the daughter nuclide will have an atomic number of
#38 + 1 = 39#
Another quick look in the periodic table will reveal that the daughter nuclide is yttrium-90,
You can thus write out the nuclear equation that describes the beta minus decay of strontium-90 like this
#color(green)(|bar(ul(color(white)(a/a)color(black)(""_ 38^90"Sr" -> ""_ 39^90"Y" + ""_ (-1)^(color(white)(aa)0)beta + bar(nu)_"e")color(white)(a/a)|)))#
Notice that mass and charge are conserved, since
#overbrace(90 = 90 + 0)^(color(blue)("conservation of mass"))" "#and #" "overbrace(38 = 39 + (-1))^(color(darkgreen)("conservation of charge"))#