If 123 mL of a 1.1 M glucose solution is diluted to 500.0 mL, what is the molarity of the diluted solution?

When studying solutions in chemistry, understanding molarity is essential. Molarity, symbolized by the capital letter 'M', stands for the concentration of a solute in a solution. It is a measure of the number of moles of solute per liter of solution. The mole is the standard unit for the amount of substance in the International System of Units (SI), and it helps chemists quantify how much of a substance they have.

Calculating molarity involves using the formula:
\[ M = \frac{\text{moles of solute}}{\text{liters of solution}} \]
To understand this better, let's consider a real-world example. If you stir a spoonful of sugar into a glass of water, you create a sugar solution. The molarity of this solution depends on the number of moles of sugar (the solute) and the volume of water (the solvent) in the glass. Generally, scientists use molarity because it allows for a standardized way to express concentrations, which is useful for preparing solutions, conducting experiments, and stoichiometric calculations.

Dilution is a crucial process in chemistry for adjusting the concentration of a solution. It involves adding more solvent to the solution without altering the amount of solute. To calculate the new concentration after dilution, the dilution formula is used:

\[ M1 \times V1 = M2 \times V2 \]
This formula states that the product of the initial molarity (M1) and the initial volume (V1) equals the product of the final molarity (M2) and the final volume (V2).

Why is this equation so practical? It allows you to calculate any one of the variables as long as the other three are known, and it's based on the conservation of the number of moles of the solute. Whether you are a scientist preparing a specific concentration for a reaction or a student in a lab exercise, understanding and applying the dilution formula is a fundamental skill in chemistry. It ensures accurateness when preparing solutions of desired molar concentrations.

Significant figures in measurements convey the precision of the recorded data. When performing calculations, it's important to consider the number of significant figures because this affects the accuracy of your final answer. The rules for significant figures are used to determine which digits in a number are meaningful and contribute to its precision.

Important Rules for Significant Figures:

• Zeros between non-zero digits are always significant.
• Leading zeros are not significant as they only indicate the position of the decimal point.
• Trailing zeros in a number are significant if the number contains a decimal point.

When multiplying or dividing numbers, the number with the fewest significant figures determines the number of significant figures in the result. This practice prevents overstating the precision of the result based on imprecise measurements and calculations that could compound errors.

Volume conversion is a fundamental aspect of solving chemistry problems, especially when dealing with solutions. Since molarity is expressed in terms of volume in liters, converting volumes from one unit to another (e.g., milliliters to liters) may be necessary to proceed with calculations. The conversion between milliliters (mL) and liters (L) is straightforward because it's based on the SI unit system where 1,000 milliliters is equal to 1 liter.

To convert milliliters to liters, the formula is:
\[ L = \frac{mL}{1000} \]
And to convert liters to milliliters:
\[ mL = L \times 1000 \]
Remembering these conversions helps prevent mistakes in calculations and ensures that all volume units align correctly. This is particularly important in lab settings where precision can greatly affect the outcome of experiments and in instances like medication dosing where the consequences of errors could be significant.