Question

use the references to access important values if needed for this question. a sample of se weighs 60.7 grams. will a sample of ga that contains the same number of atoms weigh more or less than 60.7 grams? oa sample of ga weighs less than 60.7 grams. a sample of ga weighs more than 60.7 grams. calculate the mass of a sample of ga that contains the same number of atoms. mass = g ga submit answer retry entire group 5 more group attempts remaining

Explanation:

Step1: Find molar masses

The molar mass of Se (selenium) is approximately $M_{Se}=78.96\ g/mol$, and the molar mass of Ga (gallium) is approximately $M_{Ga}=69.72\ g/mol$.

Step2: Use mole - atom relationship

Since the number of atoms is the same, the number of moles is the same (using $N = nN_A$, where $N$ is the number of atoms, $n$ is the number of moles, and $N_A$ is Avogadro's number). Let the number of moles of Se be $n_{Se}$ and of Ga be $n_{Ga}$, and $n_{Se}=n_{Ga}$. We know that $n=\frac{m}{M}$, so $\frac{m_{Se}}{M_{Se}}=\frac{m_{Ga}}{M_{Ga}}$.

Step3: Calculate mass of Ga

We are given $m_{Se} = 60.7\ g$. Rearranging the equation $\frac{m_{Se}}{M_{Se}}=\frac{m_{Ga}}{M_{Ga}}$ for $m_{Ga}$, we get $m_{Ga}=\frac{m_{Se}\times M_{Ga}}{M_{Se}}$. Substituting the values: $m_{Ga}=\frac{60.7\ g\times69.72\ g/mol}{78.96\ g/mol}$.
$m_{Ga}=\frac{60.7\times69.72}{78.96}\ g\approx 53.4\ g$. Since $53.4\ g<60.7\ g$, a sample of Ga weighs less than 60.7 grams.

Answer:

A sample of Ga weighs less than 60.7 grams.
Mass = 53.4 g Ga