Answer:
Density = 1.11 g/cm³, will not float on water
Explanation:
Assuming the other dimension missing is 4.0 cm
Then we can find the volume of the piece of wood.
Volume = Length × width × height
Volume = 6.0 cm × 3.0 cm × 4.0 cm
= 72 cm³
We are required to find the density of the wood.
Density = mass ÷ Volume
Mass of the wood = 80.0 grams
Therefore;
Density = 80.0 g ÷ 72 cm³
= 1.11 g/cm³
Hence, the density of the wood is 1.11 g/cm³
Water has a density of 1 g/cm³ and therefore the wood will not float since it is denser than water.
C6H8 + 8O2 ===> 6CO2 + 4H2O ... balanced equation
moles hexane = 54.3 g x 1 mol/80 g = 0.679 moles
moles O2 = 78.5 g x 1 mol/32 g = 2.45 moles
Limiting reactant is Oxygen (O2) since need 8 x as much as C6H8
Theoretical yield of CO2 = 2.45 mole O2 x 6 mole CO2/8mole O2 = 1.84 moles CO2
1.84 moles CO2 x 44 g/mol = 80.9 g (answer to 3 sig figs)
depending on if your question possesses this values
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The reaction between NaOH and Cu(NO₃)₂ is as follows
2NaOH + Cu(NO₃)₂ ---> 2NaNO₃ + Cu(OH)₂
Q1)
stoichiometry of NaOH to Cu(NO₃)₂ is 2:1
this means that 2 mol of NaOH reacts with 1 mol of Cu(NO₃)₂
the mass of Cu(NO₃)₂ reacted - 0.8024 g
molar mass of Cu(NO₃)₂ is 187.56 g/mol
therefore the number of Cu(NO₃)₂ moles that have reacted
- 0.8024 g/ 187.56 g/mol = 0.00427 mol
according to the stoichiometry , number of NaOH moles - 0.00427 mol x 2
then number of NaOH moles that have reacted - 0.00855 mol
In a 3.0 M NaOH solution, 3 moles are in 1000 mL of solution
Then volume required for 0.00855 mol - 1000 x 0.00855 /3 = 2.85 mL
2.85 mL of 3.0 M NaOH is required for this reaction
Q2)
Assuming that there's 100 % yield of Cu(OH)₂ , we can directly calculate the mass of Cu(OH)₂ formed from the number of moles of reactants that were used up.
Stoichiometry of Cu(NO₃)₂ to Cu(OH)₂ is 1:1
this means that 1 mol of Cu(NO₃)₂ gives a yield of 1 mol of Cu(OH)₂
the number of Cu(NO₃)₂ moles that reacted - 0.00427 mol
Therefore an equal amount of moles of Cu(OH)₂ were formed
Then amount of Cu(OH)₂ moles produced - 0.00427 mol
Mass of Cu(OH)₂ formed - 0.00427 mol x 97.56 g/mol = 0.42 g
A mass of 0.42 g of Cu(OH)₂ was formed in this reaction
Answer:
See explanation
Explanation:
Air contains a mixture of several molecules and compounds such as oxygen and carbon dioxide.