When I mean "Opus Group", I mean at least 3 consecutive opuses.
Here is a list of Compositions by Opus Number.
Op. 1, Rondo in C minor (1825)
Op. 2, Variations on "La ci darem la mano" from Mozart's opera Don Giovanni, in B-flat major, for piano and orchestra (1827)
Op. 3, Introduction and Polonaise brillante in C major for cello and piano (1829)
Op. 4 Sonata in c minor(1828)
Op. 5, Rondo à la mazur in F major (1826)
Op. 6, 4 Mazurkas (1830)
Op. 7, 5 Mazurkas (1830–1831)
Op. 8, Trio for Violin, Cello and Piano in G minor (1829)
Op. 9, 3 Nocturnes (1830–1831)
Op. 10, 12 Études (1829–1832)
Op. 11, Concerto for Piano and Orchestra No. 1 in E minor (1830)
Op. 12, Variations brillantes on "Je vends des Scapulaires" from Hérold's Ludovic, in B-flat major (1833)
Op. 13, Fantasy on Polish Airs in A major (1828)
Op. 14, Rondo à la Krakowiak in F major (1828)
Op. 15, 3 Nocturnes (1830–1833)
Op. 16, Rondo in E-flat major (1832)
Op. 17, 4 Mazurkas (1832–1833)
Op. 18, Grande valse brillante in E-flat major (1831)
Op. 19, Bolero (1833)
Op. 20, Scherzo No. 1 in B minor (1831)
Op. 21, Concerto for Piano and Orchestra No. 2 in F minor (1829–1830)
Op. 22, Andante spianato et grande polonaise brillante in E-flat major
Op. 23, Ballade No. 1 in G minor (1831–1835)
Op. 24, 4 Mazurkas (1834–1835)
Op. 25, 12 Études (1832–1836)
Op. 26, 2 Polonaises (1834–1835)
Op. 27, 2 Nocturnes (1835)
Op. 28, 24 Preludes (1836–1839)
Op. 29, Impromptu No. 1 in A flat major (1837)
Op. 30, 4 Mazurkas (1836–1837)
Op. 31, Scherzo No. 2 in B-flat minor (1837)
Op. 32, 2 Nocturnes (1836–1837)
Op. 33, 4 Mazurkas (1837–1838)
Op. 34, 3 Waltzes (1831–1838)
Op. 35, Piano Sonata No. 2 in B-flat minor ("Funeral March") (1839)
Op. 36, Impromptu No. 2 in F-sharp major (1839)
Op. 37, 2 Nocturnes (1838–1839)
Op. 38, Ballade No. 2 in F major (1836–1839)
Op. 39, Scherzo No. 3 in C-sharp minor (1839)
Op. 40, 2 Polonaises (1838–1839)
Op. 41 4 Mazurkas (1838–1839)
Op. 42, Waltz in A-flat major (1840)
Op. 43, Tarantelle in A-flat major (1841)
Op. 44, Polonaise in F-sharp minor (1841)
Op. 45, Prelude in C-sharp minor (1841)
Op. 46, Allegro de concert in A major (1832–1841)
Op. 47, Ballade No. 3 in A-flat major (1840–1841)
Op. 48, 2 Nocturnes (1841)
Op. 49, Fantaisie in F minor (1841)
Op. 50, 3 Mazurkas (1841–1842)
Op. 51, Impromptu No. 3 in G-flat major (1842)
Op. 52, Ballade No. 4 in F minor (1842)
Op. 53, Polonaise in A-flat major ("Heroic") (1842)
Op. 54, Scherzo No. 4 in E major (1842)
Op. 55, 2 Nocturnes (1843)
Op. 56, 3 Mazurkas (1843)
Op. 57, Berceuse in D-flat major (1843)
Op. 58, Piano Sonata No. 3 in B minor (1844)
Op. 59, 3 Mazurkas (1845)
Op. 60, Barcarole in F-sharp major (1845–1846)
Op. 61, Polonaise-Fantaisie in A-flat major (1845–1846)
Op. 62, 2 Nocturnes (1846)
Op. 63, 3 Mazurkas (1846)
Op. 64, 3 Waltzes (1846–1847)
Op. 65, Sonata for Cello and Piano in G minor (1845–1846)
Op. 66 Fantasie Impromptu
Op. 67 Mazurkas
Op. 68 Mazurkas
Op. 69 Waltzes
Op. 70 Waltzes
Op. 71 Polonaises
Op. 72 3 Pieces: Eccossaises, Nocturne, and Funeral March
Op. 73 Rondo in C Major
Op. 74 17 Polish Songs