Solutions Worksheets

Solution Parts

• Solutions are homogeneous mixtures (impure substances)
• Can occur with states of matter (alloy, aqueous solution, etc.)
• Solutions contain two parts (solvent and solute)

<aside> 🧪 Solvent: the part the solute dissolves in, the greater amount (unless the universal solvent is present)

Solute: the part that undergoes a phase change (often solid to aqueous), the lesser amount

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• Not chemically bonded
• Solute and solvent are not in fixed ratios (no set relationship)
• Water ($H_2O$) is the universal solvent (always the solvent whenever it is present even if it is the lesser amount)

Example: For steel composed of 99.5% Fe and 0.5% C, the solvent is iron and the solute is carbon. For a solution with 100 grams of sugar ($C_6H_{12}O_6$) and 10 grams of water ($H_2O$), the solute is sugar and the solvent is water (universal solvent).

Units of Concentration

Molarity

<aside> 🧪 $M={\frac {moles~of~solute} {L~of~solution}}$

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• Symbol is capital M
• Based on volume

Example: 6 M $HNO_3$ or “six molar nitric acid” has 6 moles of $HNO_3$ for every 1 liter

Molality

<aside> 🧪 $m={\frac {moles~of~solute} {kg~of~solvent}}$

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• Symbol is lowercase m