14
15
147.5
Answer: The sample must have passed 4 half-lives after the sample was originally formed.
Explanation: This is a type of radioactive decay and all the radioactive process follow first order kinetics.
Equation for the reaction of decay of radioisotope follows:
To calculate the initial amount of , we will require the stoichiometry of the reaction and the moles of the reactant and product.
Expression for calculating the moles is given by:
Moles of left =
Moles of
By the stoichiometry of above reaction,
1 mole of is produced by 1 mole
So, 0.7429 moles of will be produced by =
Amount of decomposed will be = 0.7429 moles
Initial amount of will be = Amount decomposed + Amount left = (0.0495 + 0.7429)moles = 0.7924 moles
Now, to calculate the number of half lives, we use the formula:
where,
a = amount of reactant left after n-half lives = 0.0495 moles
= Initial amount of the reactant = 0.7924 moles
n = number of half lives
Putting values in above equation, we get:
Taking log on both sides, we get
Answer:
4
Explanation:
Edg 2020
Answer:
A figure of the thermometer for this problem is not given so I cannot really give a specific answer. Maybe this would help. The minimum temperature would be the lowest reading possible in the thermometer. Most probably it is option C or D. Hope this helps.
Carbon is a chemicalelement with a chemical symbol "C". It has an atomic number of 6. That means a carbon atom has 6 protons, 6 neutrons, and 6electrons. Since carbon is in the second row (or second period), it has 2 electron orbits. Use the clay to make your protons and neutrons in the nucleus.
However, some factors do influence its durability, like its matrix. Furthermore, the intense use of composites and environmental factors could affect its durability and potential applications.
Read more about carbon fibre: