The mass of the substance is the product of the molar mass and the moles of the substance in the compound. The amount of the HF required in the reaction is 242 gm.
Mass is given as the product of the moles of the substance and of the molar mass of the substance in the compound.
Given,
Molar mass of Silicon dioxide = 60g/mol
mass of Silicon dioxide = 182 g
Molar mass of HF = 20 g/mol
Moles of the Silicon dioxide can be calculated as,
[tex]\begin{aligned}\rm Moles &= \rm \dfrac{mass}{molar\;mass}\\\\&= {182}{60}\\\\&= 3.03\end{aligned}[/tex]
The balanced chemical reaction can be shown as,
[tex]\rm SiO_{2} + 4HF \rightarrow SiF_{4} + 2H_{2}O[/tex]
From the reaction, it can deduce that,
1 mole of silicon dioxide reacts with 4 moles of HF
So, 3.03 moles of silicon dioxide reacts with 12.12 moles of HF
Mass of HF can be calculated as,
[tex]\begin{aligned}\text{mass of HF} &= \rm moles \times \rm molar \; mass\\\\&= 12.12 \times 20\\\\&= 242 \;\rm g\end{aligned}[/tex]
Therefore, the reaction requires 242 gm of HF.
Learn more about mass here:
https://brainly.com/question/11558651