Answer:
D. 0.75 grams
Explanation:
The data given on the iridium 182 are;
The half life of the iridium 182,
= 15 years
The mass of the sample of iridium, N₀ = 3 grams
The amount left, N(t) after two half lives is given as follows;

For two half lives, t = 2 × 
∴ t = 2 × 15 = 30


∴ The amount left, N(t) = 0.75 grams
The H+ concentration that would best describe a basic solution would be the one having values less than 10^-7. The pH of a solution is related to H+ concentration by pH = -log[H+]. Therefore, as the concentration of H+ decreases the alkalinity would rise.
Answer:
5.72 g ( 1 mol / 180.16 g ) ( 6.022 x 10^23 molecules / mole ) = 1.90x10^23 molecules
Answ
Explanation:
that is like a satelite it helps detect signals from like outer space and things