You have to use Avogadro's number which is 6.02x10^23. The units of Avogadro's number is molecules/mole so you divide the number of molecules by Avogadro's number which will give you the number of moles.
(2.0x10^22 molecules)/(6.02x10^23 molecules/mole)=0.033 moles
Here are your answers:
1. MgBr2 + Cl2 = MgCl2 + Br2
Balancing,
Already balanced.
Type of reaction: single displacement
2. Al + Fe2O3 = Al2O3 + Fe
Balancing,
2Al + Fe2O3 = Al2O3 + 2Fe
Type: single displacement reaction
3. AgNO3 + ZnCl2 = AgCl + N2O6Zn
Balancing,
2AgNO3 + ZnCl2 = 2AgCl + N2O6Zn
Type: double displacement reaction
MnO2
4. H2O2 ====== O2 + H20 [being catalyzed by manganese dioxide]
Balancing,
MnO2
2H2O2 ====== O2 + 2H2O
Type: decomposition reaction
5. Zn + HCl = ZnCl2 + H2
Balancing,
Zn + 2HCl = ZnCl2 + H2
Type: single displacement reaction
6. H2SO4 + NaOH = Na2SO4 + H2O
Balancing,
H2SO4 + 2NaOH = Na2SO4 + 2H2O
Type: Acid-base reaction
That took hella long!!! Hope it helps.
Elephants are really cool
Given : Density of Bromine = 3.12 g/mL
Formula : Density = Mass / Volume
Part A :
Given Volume = 125 mL
Density = Mass / Volume
So, Mass = Density x Volume
= 3.12 x 125
= 390 grams
Part B :
Given mass = 85.0 gm
Density = Mass / Volume
So, Volume = Mass / Density
= 85 / 3.12
= 27.24 mL
Answer:
306.6g/mol
Explanation:
To calculate molecular weight you need to know how many grams ou have in a determined amount of moles of substance. As you have the mass of the sample (1.42g), you need to find how many moles are, as follows:
The reaction of the acid HX with the base YOH is:
HX + YOH → H₂O + YX
<em>1 mole of acid reacts per mole of base.</em>
<em />
In a titration, the solution turned pink when moles base = moles acid.
Moles of base that the student added (Using the volume and molarity of the solution) are:
32.48mL = 0.03248L ₓ (0.1426 moles base / L) = 0.004632 moles of base
As the titration is in equivalence point, there are 0.004632 moles of the acid
Molecular weight (Ratio between grams of sample and its moles) is:
1.42g / 0.004632 moles =
<h3>306.6g/mol</h3>
