# GRE Subject Test: Chemistry : Reactions with Inorganic Compounds

## Example Questions

### Example Question #15 : Reaction Chemistry

What happens when a solution of  is added to a solution of ?

A decomposition reaction

A combination reaction

A synthesis reaction

A double displacement reaction

A combustion reaction

A double displacement reaction

Explanation:

The chemical reaction that would occur is provided below:

This type of reaction is called a double displacement reaction in which there is an exchange of ions between two compounds. This type of reaction usually results in the formation of a precipitate or gas. In terms of the positive ions, the  switch places  to form two new products.

### Example Question #16 : Reaction Chemistry

Which of the following types of reactions best describes the following reaction:

Alkylation

Catalytic

Synthesis

Combustion

Combustion

Explanation:

The type of reaction given is termed a combustion reaction. A combustion reaction is one that involves a substance reacting with molecular oxygen. For combustion reactions involving a hydrocarbon as given in the example, the major products are carbon dioxide and water. The word combustion is a synonym for burn.

### Example Question #17 : Reaction Chemistry

For the reaction given, identify the type of reaction taking place.

Decomposition reaction

Synthesis reaction

Combination reaction

Displacement reaction

Displacement reaction

Explanation:

A displacement reaction is one in which an atom, ion or molecule moves from one compound to another to replace an atom, ion or molecule in another compound. In the reaction given,  ion moves from  to  to form .

### Example Question #1 : Reactions With Inorganic Compounds

Determine the percentage yield of the reaction given if 12.6 grams of  is reacted excess  to give 10.4 grams of .

Explanation:

In chemistry, percentage yield is a term used to quantify the efficiency of a chemical reaction. In order to calculate this quantity, the value for the actual yield and theoretical yield is needed. The actual yield is the amount of product obtained during a chemical reaction. The theoretical yield is the maximum amount of product possible to be obtain by a chemical reaction which is based on the amount of reactants used. Below is the formula needed to calculate the percentage yield.

Convert the number of grams of  to moles:

Based on the chemical equation 1 mole of  is produced for every 1 mole of  reacted.

Convert the moles of  to grams:

### Example Question #19 : Reaction Chemistry

Determine the percentage yield of the reaction given if 21.0 grams of  is reacted with excess  to give 10.2 grams of .

Explanation:

In chemistry, percentage yield is a term used to quantify the efficiency of a chemical reaction. In order to calculate this quantity, the value for the actual yield and theoretical yield is needed. The actual yield is the amount of product obtained during a chemical reaction. The theoretical yield is the maximum amount of product possible to be obtain by a chemical reaction which is based on the amount of reactants used. Below is the formula needed to calculate the percentage yield.

Convert the number of grams of  to moles:

Based on the chemical equation 1 mole of  is produced for every 1 mole of  reacted.

Convert the moles of  to grams:

### Example Question #21 : Reaction Chemistry

Determine the theoretical yield in grams of  produced if 5.6 grams of  is reacted with excess .

Explanation:

Convert the number of grams of  to moles:

Based on the chemical equation 1 mole of  is produced for every 2 mole of  reacted.

Therefore:

Convert the moles of  to grams:

### Example Question #2 : Reactions With Inorganic Compounds

For the reaction given, identify the type of reaction taking place.

Combination reaction

Synthesis reaction

Decomposition reaction

Double displacement reaction

Double displacement reaction

Explanation:

A displacement reaction is one in which an atom, ion or molecule moves from one compound to another to replace an atom, ion or molecule in another compound. In the reaction given,  ion moves from  to . Also, ion moves from  to .

### Example Question #23 : Reaction Chemistry

Determine the percentage yield of the reaction given if 40.0 grams of  is heated to give 15.0 grams of .

Explanation:

In chemistry, percentage yield is a term used to quantify the efficiency of a chemical reaction. In order to calculate this quantity, the value for the actual yield and theoretical yield is needed. The actual yield is the amount of product obtained during a chemical reaction. The theoretical yield is the maximum amount of product possible to be obtain by a chemical reaction which is based on the amount of reactants used. Below is the formula needed to calculate the percentage yield.

Convert the number of grams of  to moles:

Based on the chemical equation 1 mole of  is produced for every 1 mole of  reacted.

Convert the moles of  to grams:

### Example Question #3 : Reactions With Inorganic Compounds

For the reaction given, identify the type of reaction taking place.

Combination reaction

Decomposition reaction

Displacement reaction

Synthesis reaction