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
<span>Acetonitrile molecules are mainly used in lithium batteries as a solvent, and is commonly found in the air from vehicle exhaust.
The geometry on</span><span> how two acetonitrile molecules would interact with each other is as follows:
_______
------- C======== N
The carbon atom has a single bond to the atom on its left side while having a triple bond on the nitrogen atom on the right side.
</span>
Negative charge
(+1)+(0)+(-1)+(-1)= -1
<span>With the addition of an electron causing a negative charge, an ion is larger than normal but with loss of an atoms electron, the positive ion is smaller.
if the atom loses an electron, the ion is relatively smaller than the atom and it becomes positive.
if the atom gains an electron, the ion is relatively bigger than the atom and it becomes negative.</span>
