Question

1. provide 2 missing symbols and 2 numbers

188
w
74
→
188
75
+

Explanation:

Step1: Identify the nuclear - decay type

This appears to be a beta - decay process. In beta - decay, a neutron in the nucleus is converted into a proton, an electron, and an antineutrino. The mass number remains the same and the atomic number increases by 1.

Step2: Write the nuclear - decay equation

The general form of beta - decay is $^{A}_{Z}X
ightarrow^{A}_{Z + 1}Y+e^{-}+\bar{
u}_{e}$. For tungsten (W) with atomic number $Z = 74$ and mass number $A = 188$, after beta - decay, the new element has atomic number $Z=75$ (rhenium, Re).
The complete nuclear - decay equation is $^{188}_{74}W
ightarrow^{188}_{75}Re+_{- 1}^{0}e+\bar{
u}_{e}$.

The two missing symbols are $_{-1}^{0}e$ (electron) and $\bar{
u}_{e}$ (antineutrino), and the two numbers are already given in the context of the nuclear - decay process. If we assume we need to fill in the full equation, we can say the two numbers for the electron are $-1$ (charge) and $0$ (mass number).

Answer:

The two missing symbols are $_{-1}^{0}e$ and $\bar{
u}_{e}$, the two numbers are $- 1$ and $0$.