Question

In an experiment, 2.54 grams of copper completely reacts with sulfur, producing 3.18 grams of copper(I) sulfide.

Answer 1

Answer:

               0.64 g of S

Solution:

               The balance chemical equation is as follow,

                                           2 Cu + S ----> Cu₂S

According to equation,

                        127 g (2 mole) Cu produces = 159 g (1 mole) of Cu₂S

So,

                                 2.54 g Cu will produce = X g of Cu₂S

Solving for X,

                     X = (2.54 g * 159 g) / 127 g

                     X = 3.18 g of Cu₂S

Now, it is confirmed that the reaction is 100% ideal. Therefore,

As,

                       127 g (2 mole) Cu required = 32 g (1 mole) of S

So,

                                2.54 g Cu will require = X g of S

Solving for X,

                      X = (2.54 g * 32 g) / 127 g

                      X = 0.64 g of S

Answer 2

Answer : The total mass of sulfur consumed will be, 0.64 grams and the chemical formula of the compound produced is, $Cu_2S$ copper oxide.

Solution :

According to the law of conservation of mass, the total mass of reactant should be equal to the total mass of product.

The balanced chemical reaction will be,

$2Cu+S\rightarrow Cu_2S$

In this reaction, copper and sulfur are the reactants and copper sulfide is the product.

Let the mass of sulfur be 'x' gram

$\text{The total mass of reactants}=\text{Total mass of copper}+\text{Total mass of sulfur}=2.54g+x$

$\text{The total mass of product}=\text{Total mass of copper sulfide}=3.18g$

According to the law of conservation of mass,

$\text{The total mass of reactants}=\text{The total mass of product}$

$2.54g+x=3.18g$

$x=(3.18-2.54)g$

$x=0.64g$

Therefore, the total mass of sulfur consumed will be, 0.64 grams and the chemical formula of the compound produced is, $Cu_2S$ copper oxide.