a) Calculate the molarity of a solution made by dissolving 12.5 grams of Na₂CrO₄ in enough water to form exactly 750 mL of solution.

검증된 단계별 안내

Step 1: Begin by determining the molar mass of Na2CrO4. To do this, add the atomic masses of all the atoms in the compound: 2 sodium (Na), 1 chromium (Cr), and 4 oxygen (O) atoms. Use the periodic table to find these values.

Step 2: Convert the mass of Na2CrO4 from grams to moles using the molar mass calculated in Step 1. Use the formula: \( \text{moles} = \frac{\text{mass (g)}}{\text{molar mass (g/mol)}} \).

Step 3: Convert the volume of the solution from milliliters to liters, as molarity is expressed in moles per liter. Use the conversion: \( 1 \text{ L} = 1000 \text{ mL} \).

Step 4: Calculate the molarity of the solution using the formula: \( \text{Molarity (M)} = \frac{\text{moles of solute}}{\text{volume of solution in liters}} \).

Step 5: Review the calculation steps to ensure accuracy and consistency in units, and understand how each part contributes to finding the molarity.

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.

영상 길이:

도움이 되었나요?

주요 개념

질문에 올바르게 답하기 위해 반드시 이해해야 하는 핵심 개념들은 다음과 같습니다.

Molarity

Molarity is a measure of concentration defined as the number of moles of solute per liter of solution. It is expressed in units of moles per liter (mol/L). To calculate molarity, one must first determine the number of moles of the solute, which can be found by dividing the mass of the solute by its molar mass, and then divide that by the volume of the solution in liters.

Molar Mass

Molar mass is the mass of one mole of a substance, typically expressed in grams per mole (g/mol). It is calculated by summing the atomic masses of all the atoms in a molecule. For Na2CrO4, the molar mass can be calculated by adding the molar masses of sodium (Na), chromium (Cr), and oxygen (O) in the correct proportions, which is essential for converting grams of the compound to moles.

Volume Conversion

Volume conversion is the process of converting a volume measurement from one unit to another, which is crucial in chemistry for accurate calculations. In this case, the volume of the solution is given in milliliters (mL) and must be converted to liters (L) for the molarity calculation, as molarity is defined in terms of liters of solution. The conversion factor is 1 L = 1000 mL.

a) Calculate the molarity of a solution made by dissolving 12.5 grams of Na2CrO4 in enough water to form exactly 750 mL of solution.