Answer:
mass of CO = 210.42 g
mass in three significant figures = 210. g
Explanation:
Given data:
mass of Fe2O3 = 0.400 Kg
mass of CO= ?
Solution:
chemical equation:
Fe2O3 + 3CO → 2Fe + 3CO2
Now we will calculate the molar mass of Fe2O3 and CO.
Molar mass of Fe2O3 = (55.845 × 2) + (16 × 3) = 159.69 g/mol
Molar mass of CO = 12+ 16 = 28 g/mol
now we will convert the kg of Fe2O3 in g.
mass of Fe2O3 = 0.400 kg × 1000 = 400 g
number of moles of Fe2O3 = 400 g/ 159.69 g/mol = 2.505 mol
mass of CO = moles of Fe2O3 × 3( molar mass of CO)
mass of CO = 2.505 mol × 84 g/mol
mass of CO = 210.42 g
mass in three significant figures = 210. g
Start with Unbalanced Equation and balance it, so...
C7H16+O2--->CO2+H2O
There are 7 C atoms on the left-hand side, so we need 7 C atoms on the right-hand side. Add a 7 in front of the CO2...7CO2+H2O on right side now.
We have fixed 16 H atoms on the left-hand side, so we need 16 H atoms on the right-hand side. Add an 8 in front of H2O to make 16 (8x2)...7CO2+8H2O on right side now.
There are 22 O atoms on the right-hand side: 14 from the CO2 and 8 from the H2O. Add an 11 in front of the O2 on the left side to make 22 (11x2).
Every formula now has a fixed coefficient. You should have a balanced equation of...
C7H16+11O2--->7CO2+8H2O
The answer is C
because plants use light energy from the sun to make their own food providing energy. The food created is a type of sugar.
This would make it definitely not A or D. The only answers left would be B and C but, technically the sunlight doesn't deliver the sugar straight to the plant so I'd go with C.
Hope that his helped!
Answer: the equation for the reaction is NH4Cl (s) --> NH3 (g) + HCl (g)
equation for heat reaction:
ΔH25° = (ΔH25° NH3 + ΔH25° HCl) - ΔH25° NH4Cl)
question 2:
the 1st and 3rd reactions are better ontained through refrence sources and the 2nd and 4th are the easiest and safest to measure in the laboratory. The 1st and rd reaction contains noxious gases this is because there is a (g) in both of the reactions. And the 2nd and 4th does NOT contain noxious gases so i assume its the safest to measure out in the lab
