☁️ Answer ☁️
Thats called weathering.
Weathering describes the breaking down or dissolving of rocks and minerals on the surface of the Earth.
Hope it helps.
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Amount of Niobium-91 initially
= 300/91 =3.2967mol
2040 years = 3 ×680 = 3 half-lives
therefore, amount left = 0.4121mol
mass of Niobium-91 remaining = 0.4121 ×91 =37.5g
Answer:
potassium.
Explanation:
located at start of period 3, will have larger radius