Answer:
2.038 seconds.
Explanation:
So, in the question above we are given the following parameters in order to solve this question. We are given a rate constant of 0.500 s^-, initial concentration= 0.860 M and final concentration= 0.310 M,the time,t =??.
Assuming that the equation for the first order of reaction is given below,that is;
A ---------------------------------> products.
Recall the formula below;
B= B° e^-kt.
Therefore, e^-kt = B/B°.
-kt = ln B/B°.
kt= ln B°/B.
Where B° and B are the amount of the initial concentration and the amount of the concentration remaining, k is the rate constant and t = time taken for the concentration to decrease.
So, we have; time taken,t = ln( 0.860/.310)/0.500.
==> ln 2.77/0.500.
==> time taken,t =2.038 seconds.
31
A dalton is the same as an atomic mass unit. And an atomic mass unit is approximately the mass of a nucleon (proton or neutron) such that the mass is 1 g/mol. So in this problem you have 15 protons and 16 neutrons, so the number of daltons is 15 + 16 = 31.
Answer:
Trial Number of moles
1 0.001249mol
2 0.001232mol
3 0.001187 mol
Explanation:
To calculate the <em>number of moles of tritant</em> you need its<em> molarity</em>.
Since the<em> molarity</em> is not reported, I will use 0.1000M (four significant figures), which is used in other similar problems.
<em>Molarity</em> is the concentration of the solution in number of moles of solute per liter of solution.
In this case the solute is <em>NaOH</em>.
The formula is:

Solve for the <em>number of moles:</em>

Then, using the molarity of 0.1000M and the volumes for each trial you can calculate the number of moles of tritant.
Trial mL liters Number of moles
1 12.49 0.01249 0.01249liters × 0.1000M = 0.001249mol
2 12.32 0.01232 0.01232liters × 0.1000M = 0.001232mol
3 11.87 0.01187 0.01187liters × 0.1000M = 0.001187 mol
Answer:
23.8
Explanation:
Formula
weight % = weight of solute/ weight of solution x 100
weight of solution = weight of salt + weight of water
weight of solution = 1.62 lb + 5.20 lb = 6.82 lb
weight % = 1.62 / 6,82 x 100
weight % = 0.238 x 100
weight % = 23.8