Answer:
1) When 69.9 g heptane is burned it releases 5.6 mol water.
2) C₇H₁₆ + 11O₂ → 7CO₂ + 8H₂O.
Explanation:
- Firstly, we should balance the equation of heptane combustion.
- The balanced equation is: <em>C₇H₁₆ + 11O₂ → 7CO₂ + 8H₂O.</em>
This means that every 1.0 mole of complete combustion of heptane will release 8 moles of H₂O.
- We need to calculate the no. of moles in 69.9 g of heptane that is burned using the relation: <em>n = mass/molar mass.</em>
n of 69.9 g of heptane = mass/molar mass = (69.9 g)/(100.21 g/mol) = 0.697 mol ≅ 0.7 mol.
<em><u>Using cross multiplication:</u></em>
1.0 mol of heptane releases → 8 moles of water.
0.7 mol of heptane releases → ??? moles of water.
<em>∴ The no. of moles of water that will be released from burning (69.9 g) of water</em> = (0.7 mol)(8.0 mol)/(1.0 mol) = <em>5.6 mol.</em>
<em>∴ When 69.9 g heptane is burned it releases </em><em>5.6</em><em> mol water. </em>
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Answer:
The rate of gas diffusion is directly proportional to temperature
Explanation:
The rate of gas diffusion is
a) directly proportional to square root of temperature
b) inversely proportional to the square root of density
c) directly proportional to pressure
d) inversely proportional time and square root of molecular mass
Thus, option A is correct
No He believed tiny particles were invisible and couldn't be changed....So No The person that believed in this was Dalton .
Answer:
339.2K
Explanation:
Using Charles law equation;
V1/T1 = V2/T2
Where;
V1 = initial volume (L)
V2 = final volume (L)
T1 = initial temperature (K)
T2 = final temperature (K)
According to the information provided in this question,
V1 = 2.97 L
V2 = 3.42 L
T1 = 21.6°C = 21.6 + 273 = 294.6K
T2 = ?
Using V1/T1 = V2/T2
2.97/294.6 = 3.42/T2
Cross multiply
2.97 × T2 = 294.6 × 3.42
2.97T2 = 1007.532
T2 = 1007.532 ÷ 2.97
T2 = 339.236
The final temperature is 339.2K
Answer:
2.07 Kcal heat must be added to completely melt the platinum.
Explanation:
Given data:
Molar heat of fusion = 4.700 Kcal / mol
Mass of platinum = 85.5 g
Heat of fusion = ?
Solution:
Formula:
ΔH = n × molar heat of fusion
n = number of moles
Now we will calculate the number of moles:
Number of moles = mass / molar mass
Number of moles = 85.5 g /195.08 g/mol
Number of moles = 0.44 mole
ΔH = n × molar heat of fusion
ΔH = 0.44 mol × 4.700 Kcal / mol
ΔH = 2.07 Kcal
