Balansiranje hemijskih jednačina

Study Notes

Chemical equations describe chemical reactions, indicating reactants and products.
The equations must be balanced, meaning the number of atoms of each element is equal on both sides.
Balancing involves adjusting coefficients (numbers before formulas) to achieve atom equality.

Synthesis/Combination: Two or more substances combine to form a single product (A + B → AB)
Decomposition: A single compound breaks down into two or more simpler substances (AB → A + B)
Combustion: A substance reacts rapidly with oxygen, often producing heat and light (fuel + O2 → products)
Single Replacement: One element replaces another in a compound (A + BC → AC + B)
Double Replacement: Two compounds exchange ions to form two new compounds (AB + CD → AD + CB)

Empirical formulas represent the simplest whole-number ratio of atoms in a compound.
Calculate from percentage composition by assuming a 100g sample.
Determine moles of each element and find the simplest ratio.
Multiply ratios if necessary to obtain whole numbers.

This is about relating amounts of chemical species (reactants and products) in chemical reactions/processes.
Use mole ratios (based on balanced chemical equations) to connect the quantities.

This involves converting between moles and mass.
Use molar mass to convert from mass to moles using the formula (mass / molar mass = moles)
Use molar mass to convert from moles to mass using the formula (moles x molar mass = mass)

Limiting reactant is the substance that is completely consumed in a reaction, limiting further product formation.
Compare reactant moles to their coefficients in the balanced equation; the one with fewer available moles is likely the limiting reactant.

Hydrates are ionic compounds with water molecules physically bonded to their structure.
Water in hydrates forms a specific ratio relative to the anhydrous compound.
Percentage of water in a hydrate calculates from the mass of water relative to the total mass/hydrate (water/hydrate x 100)