Questions: Intervals: Half Steps, Whole Steps, and Interval Numbers

Question 1

What is the interval number from C to E?

• A. Second
• B. Third
• C. Fourth
• D. It depends on whether E is sharp or flat

Answer: (B)

Interval numbers are counted by letter names, inclusive of both endpoints: C (1), D (2), E (3) — a third. The quality (major, minor, augmented) might change if E is sharp or flat, but the number is always a third. Many students count only the letters in between (just D) and incorrectly say 'second.'

Question 2

The interval from E to F is a whole step because they are adjacent letter names.

• T. True
• F. False

Answer: False

E to F is a half step (semitone), not a whole step. On the piano keyboard, there is no black key between E and F — they are physically adjacent keys. Interval number (second) and interval size in half steps are different measurements; E to F is a second but only one half step, not two.

Question 3

How many half steps are in a whole step, and how do you count half steps on a piano keyboard?

Model answer: A whole step equals two half steps. On the piano keyboard, a half step is the distance between any adjacent key (including black keys); you count every key in sequence — white and black — from one note to the other.

The piano keyboard makes half-step counting concrete: each adjacent key (regardless of color) is exactly one half step away. So C to D is two half steps (C → C# → D), while C to C# is only one. This is why beginners should use the keyboard as a physical model before working from letter names alone.