Answer:
![\boxed{_{84}^{210}\text{Po} \longrightarrow \, _{82}^{206}\text{Pb} + \,_{2}^{4}\text{He}}](https://tex.z-dn.net/?f=%5Cboxed%7B_%7B84%7D%5E%7B210%7D%5Ctext%7BPo%7D%20%5Clongrightarrow%20%5C%2C%20_%7B82%7D%5E%7B206%7D%5Ctext%7BPb%7D%20%2B%20%5C%2C_%7B2%7D%5E%7B4%7D%5Ctext%7BHe%7D%7D)
Explanation:
The unbalanced nuclear equation is
![_{84}^{210}\text{Po} \longrightarrow \, ? + \,_{2}^{4}\text{He}](https://tex.z-dn.net/?f=_%7B84%7D%5E%7B210%7D%5Ctext%7BPo%7D%20%5Clongrightarrow%20%5C%2C%20%3F%20%2B%20%5C%2C_%7B2%7D%5E%7B4%7D%5Ctext%7BHe%7D)
It is convenient to replace the question mark by an atomic symbol,
, where x = the atomic number, y = the mass number, and Z = the symbol of the element .
Then your equation becomes
![_{84}^{210}\text{Po} \longrightarrow \, _{x}^{y}\text{Z} + \,_{2}^{4}\text{He}](https://tex.z-dn.net/?f=_%7B84%7D%5E%7B210%7D%5Ctext%7BPo%7D%20%5Clongrightarrow%20%5C%2C%20_%7Bx%7D%5E%7By%7D%5Ctext%7BZ%7D%20%2B%20%5C%2C_%7B2%7D%5E%7B4%7D%5Ctext%7BHe%7D)
The main point to remember in balancing nuclear equations is that **the sums of the superscripts and the subscripts must be the same on each side of the equation**.
Then
84 = x + 2, so x = 84 - 2 = 82
210 = y + 4, so y = 206
Element 82 is lead, so the nuclear equation becomes
![\boxed{_{84}^{210}\text{Po} \longrightarrow \, _{82}^{206}\text{Pb} + \,_{2}^{4}\text{He}}](https://tex.z-dn.net/?f=%5Cboxed%7B_%7B84%7D%5E%7B210%7D%5Ctext%7BPo%7D%20%5Clongrightarrow%20%5C%2C%20_%7B82%7D%5E%7B206%7D%5Ctext%7BPb%7D%20%2B%20%5C%2C_%7B2%7D%5E%7B4%7D%5Ctext%7BHe%7D%7D)
Answer:D
Explanation:I just took it
The answer is D can I have brainliest
They have luster, good thermal and electrical conductivity, high densities and melting points, and are malleable. The only exception would be mercury most metals are solid at room temp