What material makes up ash and pumice?
1 answer:
You might be interested in
Average atomic mass of an element is the sum of atomic mass of its isotopes multiplied by their respective percentage abundance.
There are four isotopes of element X:
1. 4.350 % with mass 49.94605 amu
2. 83.79% with mass 51.94051 amu
3. 9.5% with mass 52.94065 amu
4. 2.360% with mass 53.93888 amu
Thus, average atomic mass will be:
Or,
Therefore, average atomic mass of element X will be 51.99 amu (four significant figures)
Answer:
( About ) 0.03232 M
Explanation:
Based on the units for this reaction it should be a second order reaction, and hence you would apply the integrated rate law equation "1 / [X] = kt + 1 / []"
This formula would be true for the following information -
{ = the initial concentration of X, k = rate constant, [ X ] = the concentration after a certain time ( which is what you need to determine ), and t = time in minutes }
________
Therefore, all we have left to do is plug in the known values. The initial concentration of X is 0.467 at a time of 0 minutes, as you can tell from the given data. This is not relevant to the time needed in the formula, as we need to calculate the concentration of X after 18 minutes ( time = 18 minutes ). And of course k, the rate constant = 1.6
1 / [X] = ( 1.6 )( 18 minutes ) + 1 / ( 0.467 ) - Now let's solve for X
1 / [X] = 28.8 + 1 / ( 0.467 ),
1 / [X] = 28.8 + 2.1413...,
1 / [X] = 31,
[X] = 1 / 31 = ( About ) 0.03232 M
Now for this last bit here you probably are wondering why 1 / 31 is not 0.03232, rather 0.032258... Well, I did approximate one of the numbers along the way ( 2.1413... ) and took the precise value into account on my own and solved a bit more accurately. So that is your solution! The concentration of X after 18 minutes is about 0.03232 M