What character sounds are lonely?

Today when I was looking at the Chinese character 墨(묵), which means "ink stick." I noticed that it is a combination of 黑(흑), which means "black", and 土(토), which means "dirt." Therefore, 墨(묵) literally means "black dirt." When I looked up 黑(흑) on the Naver Chinese Character dictionary, I noticed that there was only one Chinese character under the sound "흑." That made me wonder how many other sounds listed only one Chinese character. Ignoring characters that are not among the 3,500 useful characters recommended by the Korean government, here is what I found:

• 갹: 醵 a drinking party
• 귤: 橘 tangerine
• 긴: 緊 tense; taut; rigid
• 김: 金 a surname
• 끽: 喫 to drink; to eat
• 녀: 女 female; daughter; you
• 논: 論 discuss; debate
• 득: 得 to have; to possess; to obtain
• 랭: 冷 cold; chilly
• 론: 論 discuss; debate
• 룡: 龍 dragon
• 륭: 隆 to raise; high
• 름: 凜 cold; gallant; brave
• 몌: 袂 sleeve
• 본: 本 foundation
• 북: 北 north
• 솔: 率 to lead
• 쇠: 衰 become weak
• 숭: 崇 high
• 쌍: 雙 pair
• 씨: 氏 surname; clan name; Mr.
• 엔: 円 Japanese currency unit
• 왈: 曰 say; tell
• 을: 乙 bird; second
• 잡: 雜 varied; mixed
• 죄: 罪 crime
• 즐: 櫛 comb
• 층: 層 level; story; layer
• 친: 親: intimate; related; parents
• 칩: 蟄 hide; gather
• 쾌: 快 happy; cheerful; agreeable; quick
• 탱: 撑 resist; push aside
• 터: 攄 spread out; unfold; scatter
• 퍅: 愎 eccentric; fussy
• 폄: 貶 drop; lessen; belittle
• 헐: 歇 breathe; use up
• 혐: 嫌 to dislike; to be suspicious of
• 흑: 黑 black; dark
• 흥: 興 arise; raise up; start; enjoy