Answer:
8.625 grams of a 150 g sample of Thorium-234 would be left after 120.5 days
Explanation:
The nuclear half life represents the time taken for the initial amount of sample to reduce into half of its mass.
We have given that the half life of thorium-234 is 24.1 days. Then it takes 24.1 days for a Thorium-234 sample to reduced to half of its initial amount.
Initial amount of Thorium-234 available as per the question is 150 grams
So now we start with 150 grams of Thorium-234
So after 120.5 days the amount of sample that remains is 8.625g
In simpler way , we can use the below formula to find the sample left
Where
is the initial sample amount
n = the number of half-lives that pass in a given period of time.
Answer:
3.42×10²¹ of particles
Explanation:
To determine the number of particles we should know, that:
1 mol of anything contains 6.02×10²³ particles
Therefore we have to find out, how many moles corresponds to 0.332 g of NaCl.
The conversion is: 0.332 g / 58.44 g/mol = 0.00568 moles
The rule of three to determine the number of particles is:
1 mol of NaCl has 6.02×10²³ particles
0.00568 moles must have (0.00568 . 6.02×10²³ particles )/1 = 3.42×10²¹
Answer:
a. Each set of elements was arranged in special coloumns based on their mass.
Answer:
I would use soundproofing
Explanation:
Answer: Option (d) is the correct answer.
Explanation:
Endothermic process is a process in which energy or heat is absorbed by reactant species.
For example, melting of ice cubes is an endothermic process as it is absorbing heat from the surrounding and gives a cooling effect.
Thus, we can conclude that the process in which a substance gains energy is an endothermic process.