Answer:
nitrogen in atmospheres of a sample is 0.679
The empirical formula of the compound is calculated as follows
first calculate the mass of oxygen= 12-(4.09 +3.71)= 5.02g
then calculate the moles of each element, moles = mass/ molar mass
moles of K = 4.09g/39 g/mol(molar mass of K) = 0.105 moles
moles of Cl = 3.71g/35.5 g/mol(molar mass of Cl) = 0.105 moles
moles of O = 5.02g/ 16g/mol(molar mass of O) = 0.314 moles
then calculate e mole ratio by dividing each mole by the smallest number of moles ( 0.105 moles)
K=0.105/0.105= 1
Cl=0.105 /0.105=1
O= 0.314/0.105=3
therefore the empirical formula = KClO3
Answer:
When you move the burette slider to the top of a flask and add about 25 mL of NaOH to the flask, you will cause a concentration of OH- molecules. This will make the solution become a basic solution and make the litmus paper blue.
Explanation:
After reading your question, we can see that you are carrying out a test to discover the nature of the pH of a solution. This type of test uses litmus paper, which is an indicator of the presence of acids and bases, being able to determine the pH of a solution. This paper is soaked in organic ink and when placed in an acidic solution, it is red in color. However, when placed in a basic solution it has a blue color.
An acidic solution is one that has a high concentration of H+ atoms and has the ability to donate electrons. The basic solution, on the other hand, has a high concentration of OH- and has the capacity to receive electrons.
When you move the burette slider to the top of a flask and add about 25 mL of NaOH to the flask, you will cause a concentration of OH- molecules. This will make the solution become a basic solution and make the litmus paper blue, that is, the solution has the basic pH.
Missing question: What is the rate constant for the reaction?
<span>[RS2](mol L-1) Rate (mol/(L·s))
0.150 0.0394
0.250 0.109
0.350 0.214
0.500 0.438</span>
Chemical reaction: 3RS₂ → 3R + 6S.
Compare second and fourth experiment, when concentration is doubled, rate of concentration is increaced by four. So rate is:
rate = k·[RS₂]².
k = 0,438 ÷ (0,500)².
k = 1,75 L/mol·s.