Answer:
A. 433 years and 63 days
B. Iodine
C. 0.125mg
D. 1.00mg
Explanation:
A. Americium
The formula of a radioactive decay constant half life is t = 0.693/k
Where k is the decay constant.
For americium, k = 0.0016
t = 0.693/0.0016 = 433.125 apprx 433 years
For iodine, k = 0.011
Half life = 0.693/0.011 = 63 days.
B. Iodine decays at a faster rate.
C. After three half lives
For both, first half life yields a mass of 0.5mg, next yields 0.25mg, next yield 0.125mg
D. 1.00mg still remains.
Half life is high for both so the decay after one day is insignificant.
Explanation:
21.0 g of potassium reacts with 62.5 g of barium nitride, what mass of potassium nitride will be produced
The specific gravity of a sample is the ratio of the density of the sample with respect to one standard sample. The standard sample used in specific gravity calculation is water whose density is 1 g/mL. The solution having specific gravity 1.30 is the density of the sample that is 1.30 g/mL. Thus the weight of the 30 mL sample is (30×1.30) = 39 g.
Now the mass of the 10 mL of water is 10 g as density of water is 10 g/mL. Thus after addition the total mass of the solution is (39 + 10) = 49g and the volume is (30 + 10) = 40 mL. Thus the density of the mixture will be 
g/mL. Thus the specific gravity of the mixed sample will be 1.225 g/mL.
Answer:
The first ionization energy for K is less than Ca because Ca has a larger effective nuclear charge.
What of the gasses is N and the flame changes it's color from Orange to blue
