ACT: To Science or Not to Science?

The ACT Decision Tree
The Science section is now optional and no longer counts toward your Composite score (1–36). However, skipping it isn't always the right move. Use this guide to decide.

Step 1: The "Must-Take" List
Are you applying to any of the following?
Service Academies: U.S. Naval Academy, Air Force Academy, etc.
Specific Private Universities: Georgetown, Boston University, Pomona College.
Top-Tier STEM Programs: MIT, Caltech, or Georgia Tech.
YES to any? → TAKE THE SCIENCE SECTION. These schools still require or "strongly recommend" it to see your scientific reasoning.

Step 2: The "Major" Factor
What is your intended college major?
STEM Major: (Engineering, Biology, Pre-Med, Computer Science, Physics)
Action: TAKE IT. You will receive a separate STEM Score (average of Math & Science). Admissions officers for these majors want to see this specific metric.
Humanities/Arts: (English, History, Graphic Design, Music)
Action: CONSIDER SKIPPING. If the schools on your list are "Test Optional" or "Science Optional," your time is better spent perfecting your Reading and English scores.

Step 3: The "Strength" Test
How do you perform in Science?
"I’m a data whiz." If you are good at reading charts, graphs, and identifying trends quickly, take it! A high Science score (even if optional) is a "value-add" to your application.
"Science is my weakest subject." Skip it. Since it doesn’t affect your Composite score anymore, there is no reason to let a low Science score distract from a great 3-section Composite.

"Optional" does not mean "Irrelevant." If you are unsure, take it once. If you do great, send the score. If you don't, you can take the 'Core-Only' version next time and your Composite score won't be dragged down by the Science result.

If you...	Take Science	Skip Science
Goal	Apply to competitive STEM or Top-20 schools.	Maximize the composite score with less fatigue.
Score Impact	Calculated into a STEM Score only.	Zero impact on your 1–36 Composite.
Test Length	Adds 40 minutes to your day.	Finished in approx. 2 hours.
Strategy	Shows "Scientific Reasoning" skills.	Allows 100% focus on English, Math, and Reading.

Chemistry - Molarity

In chemistry, we often need to know exactly how much of a substance (the solute) is dissolved in a liquid (the solvent). To measure this precisely, chemists use Molarity (M). Molarity is defined as the number of moles of solute per liter of solution.

THE FORMULA

M = n / V
Where:
M = Molarity (units are mol/L, often abbreviated as M)
n = Number of moles of solute (measured in mol)
V = Total volume of the solution (measured in Liters, L)

IMPORTANT RULES TO REMEMBER

- Volume MUST be in Liters: If a problem gives you milliliters (mL), you must convert it by dividing by 1000. For example, 500 mL = 0.5 L.

- Grams to Moles: If a problem gives you the mass of the solute in grams, you must use the molar mass from the Periodic Table to convert it to moles first (grams divided by molar mass = moles).

PRACTICE PROBLEMS

Problem 1: What is the molarity of a solution that contains 0.75 moles of NaCl dissolved in 1.5 Liters of water?

Problem 2: A student dissolves 2.0 moles of MgCl2 in enough water to make 400 mL of solution. What is the molarity?

Problem 3: You weigh out 40.0 grams of Sodium Hydroxide (NaOH). You dissolve it in water to create a total volume of 2.0 Liters. What is the molarity of this solution? 

ANSWER KEY

Problem 1:
Work: M = 0.75 mol / 1.5 L
Answer: 0.5 M

Problem 2:
Work: 400 mL = 0.4 L. Then, M = 2.0 mol / 0.4 L
Answer: 5.0 M

Problem 3:
Work Step 1: 40 g / 40 amu = 1.0 mol
Work Step 2: M = 1.0 mol / 2.0 L
Answer: 0.5 M