Plz help on both I will mark brainest and explain how you got it

as much as i can see i think it goes like this?:

1.H202--> H20+02

Answer is 2,2,1 bc

1.when you add 2 to H202 its 2H202 so H is 4 and O is 4,

2.when you add 2 to H20 its 2H20 so H is 4 and O is 2 (so H is done and good on both sides we have 4 H)

3. and then when you add 1 to O2 its still O2 you dont need to add anything bz when you add the 2O from 2H2O with O2 its 4 O so everything's good (i explained it a bit messy so you can message me if you got questions)

2. Ag20->Ag+ O2

answer is 2,4,1

1.when you add 2 to Ag2O2 it becomes 2Ag2O (so Ag is 4 and O is 2)

2. you add 4 to Ag bc on the left side when you added 2 Ag became 4 so now its equal on both sides (they're both 4)

3.you add 1 (basically dont add anything bc you dont write 1 just leave it as O2) bc on left side you got O2 and the same on right side (if you got questions message me:))

part 1: the half-life of the element is 22 years.

part 2: it will take 132.02 year for the sample to decay from 308.0 g to 4.8125 g.

explanation:

part 1: there are two ways to determine the half life time.

first way: the half life time can be determined directly from its definition as it is the time required for the sample to decay to its half concentration.

from the data the initial concentration was 45.0 g and decayed to its half value (22.5 g) in 22.0 years.

second way: the radio active decay is considered first order reaction so we can use the laws of first order reactions.

k = (1/t) ln (a/a-x), where k is the rate constant of the reaction,

t is the time of the reaction

a is the initial concentration of the reactant

a-x is the remaining concentration at time (t)

a = 45.0 g the initial concentration at t = 0 year.

at t = 22 year, a-x = 22.5 g

then k = (1/22 year) ln (45.0 g/ 22.5 g) = 0.0315 year-1.

the half-life time (t1/2) = ln 2/ k = 0.693/ k =0.693/ 0.0315 = 22 years.

part 2:

using the same law k = (1/t) ln (a/a-x),

using the given data; a = 308.0 g and a-x = 4.8125 g and the calculated k from the part 1 (k = 0.0315 year-1)

t = (1/k) ln (a/a-x) = (1/0.0315) ln (308.0/ 4.8125) = 132.02 years

there all right good

explanation: