Question

How many moles of HCI are neede to prepare 150 mL of a 1.2 M
solution?​

Answer 1

0.18 moles HCl

Step-by-step explanation:

Answer 2

0.18 moles HCl

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

Unit 0

• Conversion: 1000 mL = 1 L

Aqueous Solutions

• Molarity = moles of solute / liters of solution

Step-by-step explanation:

Step 1: Define

150 mL

1.2 M

x moles

Step 2: Identify Conversions

mL to L conversion

Step 3: Convert

`\displaystyle 150 \ mL((1 \ L)/(1000 \ mL) )` = 0.15 L

Step 4: Solve for Moles

1. Substitute [Molarity]:
   `\displaystyle 1.2 \ M = (x \ moles \ HCl)/(0.15 \ L)`
2. Isolate x:
   `\displaystyle 0.18 \ moles \ HCl = x`
3. Rewrite:
   `\displaystyle x = 0.18 \ moles \ HCl`

Step 5: Check

We are given 2 sig figs. Follow sig fig rules and round.

Since our final answer is in 2 sig figs, there is no need to round.