Answer:
S.
Explanation:
North and South must always be opposite of each other.
Send answer choices. Wanna make sure My answer is correct
Answer:
Ionic
Explanation:
Sodium is Metal, Oxygen is Non-metal. Non-metals and metals are automatic Ionic bonds
Answer:
Hydrogen is an element
Explanation:
Hydrogen is an element with only hydrogen atoms, whereas air, carbon dioxide, and water are all made up of multiple elements with different types of atoms.
An exponential decay law has the general form: A = Ao * e ^ (-kt) =>
A/Ao = e^(-kt)
Half-life time => A/Ao = 1/2, and t = 4.5 min
=> 1/2 = e^(-k*4.5) => ln(2) = 4.5k => k = ln(2) / 4.5 ≈ 0.154
Now replace the value of k, Ao = 28g and t = 7 min to find how many grams of Thalium-207 will remain:
A = Ao e ^ (-kt) = 28 g * e ^( -0.154 * 7) = 9.5 g
Answer 9.5 g.
