⚛️3️⃣7️⃣

#rubidium #element 37 #atomic number 37 #chemical element #RB

⚛️🕰️⏱️

#rubidium #atomic clock #frequency standard #timekeeping #rb clock

⚛️⬜️💧💥🔥

#rubidium #alkali metal #reactivity #reaction with water #chemical element #group 1