Chapter 32 - Chemical Formulas and Chemical Equations Flashcards
How can we tell if a symbol represents a molecule or an element?
When a symbol is followed by a small number, this represents a molecule of that element, e.g. H2 represents a molecule of hydrogen
What is a chemical formula used to represent?
A compound or a molecule of a compound, e.g. FeS = iron sulfide
What are the formulas for the following covalent compounds?
- hydrogen chloride
- water
- methane (natural gas)
- carbon dioxide
- hydrogen peroxide
- HCl
- H2O
- CH4
- CO2
- H2O2
What are the formulas for the following ionic compounds?
- sodium chloride - calcium carbonate (marble, chalk)
- magnesium oxide - manganese dioxide
- iron sulfide - sodium hydroxide
- calcium chloride - calcium hydroxide
- copper sulfate
- NaCl - CaCO3
- MgO - MnO2
- FeS - NaOH
- CaCl2 - Ca(OH)2
- CuSO4
What are the two types of equations in chemistry?
- word equations
- chemical equations
What is the word equation for when hydrogen gas is burned in oxygen?
Hydrogen + oxygen —> water
+ = ‘and’ & —> = ‘changes into’
What are the chemicals that react together in the chemical reaction called? (General name)
Reactants
What is the substance on the right of the word equation usually referred to as?
The product
Describe chemical equations
Similar to word equations, but use symbols (for elements) and formulas (for compounds)
Give two examples of chemical equations
C + O2 —> CO2
HCl + NaOH —> NaCl + H2O
Give an example of a balanced equation
C + O2 —> CO2
What is a balanced equation? (Definition 😋)
A balanced equation is one in which the total number of atoms of each element on the left-hand side of the equation is equal to the total number of atoms on the right-hand side of the equation
Balance the chemical equation of burning magnesium in oxygen to form magnesium oxide
Mg + O2 —> MgO
2Mg + O2 —> 2MgO
