Question

How many moles are present in 54.8 mL of mercury if the density of mercury is 13.6 g/mL?​

Answer 1

3.72 mol Hg

General Formulas and Concepts:

Chemistry - Atomic Structure

• Reading a Periodic Table
• Using Dimensional Analysis
• Density = Mass over Volume

Step-by-step explanation:

Step 1: Define

D = 13.6 g/mL

54.8 mL Hg

Step 2: Identify Conversions

Molar Mass of Hg - 200.59 g/mol

Step 3: Find

13.6 g/mL = x g / 54.8 mL

x = 745.28 g Hg

Step 4: Convert

`745.28 \ g \ Hg((1 \ mol \ Hg)/(200.59 \ g \ Hg) )` = 3.71544 mol Hg

Step 5: Check

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

3.71544 mol Hg ≈ 3.72 mol Hg