When 15.0 g of chlorine is added to acetylene, C2H2, 16.8 g of 1,1,2,2-tetrachloroethane, C2H2Cl4, is formed:

2 Cl2 (g) + C2H2 (g) → C2H2Cl4 (l)

What is the percent yield of this reaction?

94.6%

Explanation:

Step 1:

The balanced equation for the reaction. This is given below:

2Cl2(g) + C2H2(g) → C2H2Cl4(l)

Step 2:

Determination of the mass of Cl2 that reacted and the mass of C2H2Cl4 produced from the balanced equation.

This is illustrated below:

Molar Mass of Cl2 = 2 x 35.5 = 71g/mol

Mass of Cl2 from the balanced equation = 2 x 71 = 142g

Molar Mass of C2H2Cl4 = (12x2) + (2x1) + (35.5x4) = 168g.

Mass of C2H2Cl4 from the balanced equation = 1 x 168 = 168g

Therefore, 146g of Cl2 reacted and 168g of C2H2Cl4 were produced from the balanced equation.

Step 3:

Determination of the theoretical yield of C2H2Cl4.

This is illustrated below:

From the balanced equation above,

146g of Cl2 reacted to produce 168g of C2H2Cl4.

Therefore, 15g of Cl2 will react to produce = (15 x 168)/142 = 17.75g of C2H2Cl4.

Therefore, the theoretical yield of C2H2Cl4 is 17.75g

Step 4:

Determination of the percentage yield of C2H2Cl4.

The percentage yield of C2H2Cl4 can be obtained as follow:

Actual yield of C2H2Cl4 = 16.8g

Theoretical yield of C2H2Cl4 = 17.75g

Percentage yield of C2H2Cl4 =..?

Percentage yield = Actual yield /Theoretical yield x 100

Percentage yield = 16.8/17.75 x 100

Percentage yield = 94.6%

Therefore, the percentage yield of C2H2Cl4 is 94.6%

the density of gold = 19.3 g/cm3

the relation between density and mass and volume is

density = mass / volume

given :

mass of gold = 13 g

density = 13g / volume = 19.3

volume = 13 /19.3 = 0.67 cm^3

thus volume of gold nugget = 0.67 cm^3

they are all solids.