Question

1. In a recent study, a scientist claimed that his new molecule which contains 16.6 % of element (A),  57.3 % of Element (D), 15.1 % of element (J) and 11.0 % of element (Q) could be a cure for the covid -19. The atomic mass of these imaginary elements are given as;  A=  33.133 g/mol, D = 114.14 g/mol, J= 15.006 g/mol and Q= 10.996 g/mol.  Find the empirical formula of the compound.

Answer 1

Answer:

Empirical formula of compound is A₁D₁J₂Q₂.

Calculation:

Start with the number of grams of each element, given in the problem.

If percentages are given, assume that the total mass is 100 grams so that

the mass of each element = the percent given.

16.6 g element A;

57.3 g element D;

15.1 g element J;

11.0 g element Q.

Convert the mass of each element to moles using the given atomic mass we get,

16.6 g A × 1 mol/33.133 g = 0.501 mol A;

57.3 g D × 1 mol/114.14 g = 0.502 mol D;

15.1 g J × 1 mol/15.006 g = 1.006 mol J;

11.0 g Q × 1 mol/10.996 g = 1.003 mol Q.

Divide each mole value by the smallest number of moles calculated (0.501). Round to the nearest whole number.

0.501/0.501 mol A = 1;

0.502/0.501 mol D = 1.002 $\simeq$ 1;

1.006/0.501 mol J = 2.008 $\simeq$ 2;

1.003/0.501 mol Q = 2.002 $\simeq$ 2,

So the empirical formula is A₁D₁J₂Q₂.