Answer:
The amount in grams of hydrogen gas produced is 0.551 grams
Explanation:
The parameters given are;
Number of atoms of potassium, aₙ = 3.289 × 10²³ atoms
Chemical equation for the reaction is given as follows;
2K + 2H₂O 
KOH + H₂
Avogadro's number, 
, regarding the number of molecules or atom per mole is given s follows;
= 6.02 × 10²³ atoms/mole
Therefore;
The number of moles of potassium present = 3.289 × 10²³/(6.02 × 10²³) = 0.546 moles
2 moles of potassium produces one mole of hydrogen gas, therefore;
1 moles of potassium produces 1/2 mole of hydrogen gas, and 0.546 moles of potassium will produce 0.546/2 moles of hydrogen which is 0.273 moles of hydrogen gas
The molar mass of hydrogen gas = 2.016 grams
Therefore, 0.273 moles will have a mass of 0.273×2.016 = 0.551 grams.
The amount in grams of hydrogen gas produced = 0.551 grams.
Answer: The mass percentage of 
is 5.86%
Explanation:
To calculate the mass percentage of in the sample it is necessary to know the mass of the solute ( in this case), and the mass of the solution (pesticide sample, whose mass is explicit in the letter of the problem).
To calculate the mass of the solute, we must take the mass of the 
precipitate. We can establish a relation between the mass of and using the stoichiometry of the compounds:
Since for every mole of Tl in there are two moles of Tl in , we have:
Using the molar mass of we have:
Finally, we can use the mass percentage formula:
Answer:
300 mM
Explanation:
In order to solve this problem we need to calculate the line of best fit for those experimental values. The absorbance values go in the Y-axis while the concentration goes in the X-axis. We can calculate the linear fit using Microsoft Excel using the LINEST function (alternatively you can write the Y data in one column and X data in another one, then use that data to create a dispersion graph and finally add the line of best fit and its formula).
The <u>formula for the line of best fit for this set of data is</u>:
So now we <u>calculate the value of </u><u><em>x</em></u><u> when </u><u><em>y</em></u><u> is 1.50</u>:
Explanation:
South America land mass serves as a deflector for the South equatorial current. This deflection the current causes them to move in a different direction. If the Continent were not present the direction of the South equatorial current would not change and it would continue to flow in the west.
Answer:
Nervous system directs your body to swear to release heat.
Explanation:
Sweat maintains homeostasis when overheating.
