Chemical Reactions Flashcards
Define chemical formula.
It is a combination of symbols representing the elements that make up a compound.
* They are convenient.
* They are based on the formula unit.
Define formula unit.
The smallest collection of atoms that gives us two important information:
1. The identity of the element that makes up the compound.
2. The relative amount of different atoms in one molecule of the compound.
Define hydrates.
Hydrates are compounds where one or more water molecules form an integral part of its structure.
Define formula mass.
It is the sumof the atomic weights of all the atoms in the chemical formula of the molecule.
What is a chemical equation?
A chemical equation represents a chemical change.
What does a chemical equation tell us?
- If the reaction occurs.
- The reactants and the products.
- The relative number of moles of each reactant and product.
- The physical states of each reactant and product.
- Reaction conditions such as catalysts, heat, light, temperature, etc.
- The mass of reactants in equal to the mass of the procucts- Law of Conservation of Mass.
What do subscripts and coefficients indicate?
Coefficients- The number of molecules there are of a specific chemical.
Subscript- The relative number of atoms in a molecule.
What are reactants and products?
Reactants-
* They are the starting substances that undergo change to give new substances in a chemical reaction.
* Always written to the left.
Products-
* The new substances produced after the the chemical reaction.
* Always written to the left.
What are the features of a chemical equation?
- Reactants and products are represented using their chemical symbols.
- Reactants are written to the left and products to the right.
- The physical state of the reactants and products is specified by parethesis.
- A triangle above the arrow represents that the reaction requires energy.
- A chemical equation is balanced.
What is a chemical reaction?
- A chemical reaction takes place when one or more substances are changed into others.
- It involves a change in the arrangement of atoms or molecules to give products with different composition and properties.
- Involves breaking and formation of bonds.
What are the kinds of patterns in chemical reactions?
- Combination
- Decomposition
- Single Displacement
- Double Displacement
What is the difference between single displacement and double displacement?
Single displacement- A single atom replaces another in a molecule to give a new substance.
Double displacement- Molecules eschange atoms to give new products.
What are the types of chemical reactions?
- Precipitation
- Reaction with Oxygen
- Acid-Base reactions
- Redox Reactions
What is a precipitation reaction?
Solutions undergo chemical change to give insoluble products.
Give an example of a preceipitation reaction in the human body.
Formation of kidney stones due to the precipitation of calcium oxalate.