Q. 5.82 - An Introduction to General, Organic, and Biological Chemistry

Question

One of the most recent trans uranium elements, oganesson-$294 (Og-294)$, atomic number $118$, was prepared by bombarding $californium-249$ with another isotope. Complete the following equation for the preparation of this new element: $(5.2)$

data-custom-editor="chemistry" $?+{}_{98}{}^{249}\mathrm{Cf}\to {}_{118}{}^{294}\mathrm{Og}+3{}_0{}^1\mathrm{n}$

Step-by-Step Solution

Answer

The whole nuclear equation:

${}_{20}{}^{48}\mathrm{Ca}+{}_{98}{}^{249}\mathrm{Cf} \to {}_{118}{}^{294}\mathrm{Uuo}+3{}_0{}^1\mathrm{n}$ 

Step 1: Given Information

By bombarding $californium-249$ with another isotope, $ununoctium-294$ with atomic number $118$ was created.

The following is an incomplete nuclear equation:

data-custom-editor="chemistry" $?+{}_{92}{}^{249}\mathrm{Cf}\to {}_{118}{}^{294}\mathrm{Uuo}+3{}_0{}^1\mathrm{n}$

Calculate the missing isotope's mass number first.

$Mass number of old nucleus=(mass number of Uuo)-(mass number of Cf)$

Substitute the following value in the equation:

 $$\begin{gathered} Mass number of old nucleus =\left[\right(294)+(3\left)\right] -\left[249\right] \\ =48 \end{gathered}$$

Step 2: Given Explanation

Determine the atomic number of the old nucleus.

$$\begin{gathered} Atomic number of old nucleus=(atomic number of Uuo)+( atomic number of 3 n)-(atomic number of Cf) \\ Atomic number of old nucleus=\left[\right(118)+(0\left)\right] -\left[98\right] \\ =20 \end{gathered}$$

Step 3: Conclusion

Find the former element's symbol.

Calcium has the atomic number $20$ in the periodic table. $48$ is the mass number.

data-custom-editor="chemistry" ${}_{20}{}^{48}\mathrm{Ca}$  is the symbol for this isotope.

The following is the whole nuclear equation:

${}_{20}{}^{48}\mathrm{Ca}+{}_{98}{}^{249}\mathrm{Cf} \to {}_{118}{}^{294}\mathrm{Uuo}+3{}_0{}^1\mathrm{n}$