Answer:
The concentration the student should write down in her lab is 2.2 mol/L
Explanation:
Atomic mass of the elements are:
Na: 22.989 u
S: 32.065 u
O: 15.999 u
Molar mass of sodium thiosulfate, Na2S2O3 = (2*22.989 + 2*32.065 + 3*15.999) g/mol = 158.105 g/mol.
Mass of Na2S2O3 taken = (19.440 - 2.2) g = 17.240 g.
For mole(s) of Na2S2O3 = (mass taken)/(molar mass)
= (17.240 g)/(158.105 g/mol) = 0.1090 mole.
Volume of the solution = 50.29 mL = (50.29 mL)*(1 L)/(1000 mL)
= 0.05029 L.
To find the molar concentration of the sodium thiosulfate solution prepared we use the formula:
= (moles of sodium thiosulfate)/(volume of solution in L)
= (0.1090 mole)/(0.05029 L)
= 2.1674 mol/L
H2SO4 or hydrogen sulfate is an acid and NaOH or sodium hydroxide is a base or an alkali. The reaction between an acid and a base or alkali produces a salt and water. The reaction between these substances is shown below:
H2SO4 (aq) + 2NaOH (aq)------>2H20 (L) + Na2SO4 (aq). The salt produced in this reaction is sodium sulfate.
Answer:
There would be three Lithium atoms per one Nitrogen atom.
3:1
Li3N (Lithium Nitride)
Explanation:
Group 15 elements usually have 5 valence electrons, and every atom wants to have a full valence shell of valence electrons. So, nitrogen can get three electrons from each Lithium atom in order to get a full octet.
<span>Too much B. potassium can
slow and eventually stop the heart, and supplements should be taken only
under the care of a physician.
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