Answer: The student should obtain <u>1.103 g of aluminum oxide </u>
Explanation:
- First we write down the equations that represent the aluminum hydroxide precipitation from the reaction between the aluminum nitrate and the sodium hydroxide:
Al(NO3)3 + 3NaOH → 3NaNO3 + Al(OH)3
Now, the equation that represents the decomposition of the hydroxide to aluminum oxide by heating it.
2Al(OH)3 → Al2O3 + 3H2O
- Second, we gather the information what we are going to use in our calculations.
Volumen of Al(NO3)3 = 40mL
Molar concentration of Al(NO3)3 = 0.541M
Molecular Weight Al2O3 = 101.96 g/mol
- Third, we start using the molar concentration of the aluminum nitrate and volume used to find out the total amount of moles that are reacting
then we use the molar coefficients from the equations to discover the amount of Al2O3 moles produced
finally, we use the molecular weight of the Al2O3 to calculate the final mass produced.
Answer:
118.776 mmHg
Explanation:
The equation of the reaction is;
C4H10(g) + 13/2 O2(g) ------> 4CO2(g) + 5H20(g)
Now the mole ratio according to the balanced reaction equation is;
1 : 6.5 : 4 : 5
Hence, the total number of moles present = 1 + 6.5 + 4 + 5 = 16.5 moles
Mole fraction of water vapour = 5/16.5 = 0.303
We also know that;
Partial pressure= mole fraction * total pressure
Partial pressure of H20(g) = 0.303 * 392 mmHg = 118.776 mmHg
Answer is: the average atomic mass 217.606 amu.
Ar₁= 203.973 amu; the average atomic mass of isotope.
Ar₂ = 205.9745 amu.
Ar₃ = 206.9745 amu.
Ar₄ = 207.9766 amu.
ω₁ = 1.40% = 0.014; mass percentage of isotope.
ω₂ = 24.10% = 0.241.
ω₃ = 22.10% = 0.221.
ω₄ = 57.40% = 0.574.
Ar = Ar₁ · ω₁+ Ar₂ · ω₂ + Ar₃ · ω₃ + Ar₄ · ω₄.
Ar = 203.973 amu · 0.014 + 205.9745 amu · 0.241 + 206.9745 amu · 0.221 + 207.9766 amu · 0.574.
Ar = 2.855 amu + 49.632 amu + 45.741 amu + 119.378 amu.
Ar = 217.606 amu.
But abundance of isotopes is greater than 100%.
It should be lead, with the fourth isotope weighs 207.9766 amu and an abundance of 52.40.
36 divided by 12 is 3. you need three times as much of the recipe to make 36 brownies. The answer is B
The factors that affect geometry of a molecule are
> The number of bonding electron pairs around the central atom.
> The number of pairs of non-bonding ("lone pair") electrons around the central atom.
