Question

2.25g Sample of scandium metal is reacted with excess hydrochloric acid to produce 0.1502g hydrogen gas, which is the formula of the scandium chloride produced in the reaction?

Short answer

The formula for the scandium chloride is ScCl₃

Step-by-step solution

Step 1:Values of Hydrogen

The mass of hydrogen gas is 0.1502g

The molar mass of hydrogen is 1.008g

Finding moles of hydrogen

Moles of hydrogen$=\frac{Mass}{Molarmass}$

On applying the value

Moles of hydrogen$=\frac{0.1502g}{1.008g}$

Moles of hydrogen = 0.15 moles

Step 3:Reasoning of Hydrogen

Hydrogen is comes from HCL. Therefore, 1 mole of HCL provides 1 mole of hydrogen and 1 mole of chlorine. Chlorine is reacted with scandium and also the moles of chlorine is equal to the moles of hydrogen.

Therefore, the moles of chlorine is

Finding the moles of Scandium

Moles of Scandium$=\frac{Mass}{Atomicmass}$

On applying the value

Moles of Scandium$=\frac{2.25g}{44.95g}$

Moles of Scandium = 0.05moles

Conclusion

The formula for scandium chloride is ScCl₃