Answer:
I think it is b) NOT SURE
Explanation:
It has many different uses like being used to make the tube of a vacuum cleaner and also can be used to make oil in space crafts.
Answer is 0.7 g
Reason: Given: mass of Fe = 5.60 gWe know that, half life of Fe-53 = t1/2 (Fe-53) = 8.51 min.
Thus, after 25.53 mins, number of half life passed = 25.53/8.51= 3
Now, Amount left after first half life = 5.60g/2 = 2.80 g
Amount left after second half life = 2.80g/2 = 1.40 g
Amount left after third half-life = 1.40g/2 = 0.7g.
The answer is C: How long does it take distilled water to evaporate from a 5” diameter container?
Answer:
The activity of 50mg of Sr is 
Explanation:
Every nuclear disintegration follows the first order rate, thus the half-life (t1/2) is 
where k is the constant of the reaction.
<em>Considering 1 year equals 3.15x107 seconds</em>
For Sr with t1/2 = 
, the constant of the reaction is
The activity (A) of a nucleus is 
where N is the number of nucleus. Sr molecular mass is 87.6g/mol and every mol contains 6.023x1023 atoms, thus
Therefore, the activity of 50mg of Sr is
