Question

Calculate the percent error, with correct sig figs, in the atomic weight if the mass of a Zn electrode increased by 0.3681 g and 6.514x10-3 moles of Zn was produced. Select the response with the correct Significant figures. You may assume the molar mass of elemental zinc is 65.38 g/mol. Refer to Appendix D as a guide for this calculation.

Answer 1

Answer:

the percent error is -13.5%  

Explanation:

Given the data in the question;

Exact atomic weight = 65.38 g/mol

For approx

increased mass = 0.3681 g

moles = 6.514 x 10⁻³

we know that; moles = mass / (Atomic mass )

so

Atomic mass_$_{approx$ = mass / moles

Atomic mass_$_{approx$  = 0.3681 / 6.514 x 10⁻³

Atomic mass_$_{approx$  = 56.509

so approx atomic weight = 56.51 g/mol

we know that;

% error = ( [approx - exact] / exact ) × 100

we substitute

% error = ( [56.51 - 65.38]  / 65.38 ) × 100

% error = (-8.87 / 65.38 ) × 100

% error = ( -0.1356684 ) × 100  

% error = -13.5%  

Therefore, the percent error is -13.5%