Question

How many grams of magnesium sulfate (MgSO4) are dissolved in 0.965 L of a 0.0575 M solution?

Answer 1

Answer:

6.68 g MgSO₄

General Formulas and Concepts:

Math

Pre-Algebra

Order of Operations: BPEMDAS

1. Brackets
2. Parenthesis
3. Exponents
4. Multiplication
5. Division
6. Addition
7. Subtraction

• Left to Right

Chemistry

Aqueous Solutions

• Molarity = moles of solute / liters of solution

Atomic Structure

• Reading a Periodic Table
• Using Dimensional Analysis

Explanation:

Step 1: Define

0.965 L

0.0575 M

Step 2: Identify Conversions

Molar Mass of Mg - 24.31 g/mol

Molar Mass of S - 32.07 g/mol

Molar Mass of O - 16.00 g/mol

Molar Mass of MgSO₄ - 24.31 + 32.07 + 4(16.00) = 120.38 g/mol

Step 3: Find MgSO₄

1. Substitute [M]:                     0.0575 M = x / 0.965 L
2. Isolate x:                              0.055488 mol MgSO₄ = x
3. Rewrite:                               x = 0.055488 mol MgSO₄

Step 4: Convert

$\displaystyle 0.055488 \ mol \ MgSO_4(\frac{120.38 \ g \ MgSO_4}{1 \ mol \ MgSO_4} )$ = 6.67959 g MgSO₄

Step 5: Check

We are given 3 sig figs as our lowest. Follow sig fig rules and round.

6.67959 g MgSO₄ ≈ 6.68 g MgSO₄