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質量数 (しつりょうすう) Japanese meaning | Kotomora

質しつ量りょう数すう

し

つ

りょ

う

す

う

Meanings

1

mass number

physics›chemistry›

Technical term in physics and chemistry; the total number of protons and neutrons in an atomic nucleus.

炭たん素そ14の

質しつ

量りょう

数すう

は

14

です

。

The mass number of carbon-14 is 14.

Kanji

質substance, quality, matter
量quantity, measure, weight
数number, strength, fate

Related words

原げん子し番ばん号ごう
原子番号 is the atomic number (number of protons), while 質量数 is the mass number (protons + neutrons).
原げん子し量りょう
原子量 is the atomic weight (average mass of isotopes), whereas 質量数 is an integer count for a specific isotope.

Built from

質しつ量りょう+数すう

Etymology

Compound of 質量 (mass) and 数 (number), a straightforward calque from English 'mass number'.