Answer:
0.9483 grams of manganese dioxide should be added to excess HCl.
Explanation:
Pressure of the chlorine gas = P = 795 Torr = 1.046 atm (1 atm = 760 Torr)
Volume of the chlorine gas = V = 255 ml = 0.255 L
Temperature of the chlorine gas = T = 25°C= 298.15 K
Moles of chlorine gas = n
Using ideal gas equation:
PV = nRT

n = 0.01090 mol

According to reaction , 1 mole of chlorine gas is obtained from 1 mole of manganese dioxide.
Then 0.01090 moles of chlorine gas will be obtained from:
manganese dioxide
Mass of 0.01090 moles of manganese dioxide:
0.01090 mol × 87 g/mol = 0.9483 g
Answer:
1. 0.338 moles of Fe
2. 0.700 moles of Fe
3. 48.3%
Explanation:
This is the reaction:
Fe₂O₃ + 3C → 2Fe + 3CO
We were told that we produce 18.9 g of Fe. Let's convert the mass to moles:
18.9 g . 1mol/ 55.85 g = 0.338 moles of Fe
Let's make a rule of three; ratio is 1:2.
1 mol of oxide can produce 2 moles of elemental iron
Then, 0.350 moles must produce (0.350 .2) / 1 = 0.700 moles of Fe
Let's determine the percent yield:
(Yield produced /Theoretical Yield) . 100 = 48.3 %
Answer:
7.44x10⁻³ mol/L and 744 ppm
Explanation:
Let's assume that the hardness of the water is totally from Ca⁺² ions only(the hardness is the measure of Ca⁺² and Mg⁺² ions). The titration with EDTA will form a complex. The EDTA is always in 1:1 proportion, so the number of moles of it will be the number of moles of Ca⁺², which will be the number of moles of CaCO₃.
n = 0.0124 L * 0.0300 mol/L
n = 3.72x10⁻⁴ mol
The molarity is the number of moles divided by the volume (0.05 L)
M = 3.72x10⁻⁴/0.05
M = 7.44x10⁻³ mol/L
1 part per million = 1 mg/L. The molar mass of the CaCO₃ is 100 g/mol, so the mass of it is:
m = 3.72x10⁻⁴ mol * 100 g/mol
m = 0.0372 g = 37.2 mg
Then, the ppm:
37.2/0.05 = 744 ppm
double displacement
bcoz each of the reactants combines with other reactants to obtain the product
Cm3 is Centimeter to the 3 power or Cubic Centimeter, just like for figuring concrete you need to know the volume of the pour expressed in cubic yards, length x width x height.
cm3 is centimeters instead of yards.
<span>So 25 grams/5 cubic centimeters (CM3) = 5
HOPE THIS HELPED</span>