Answer:
- <em>Option d. Its empirical formula is CH</em><em>₂</em><em>.</em>
Explanation:
The percent composition of the compound allow you to calculate the empirical formula of the compound but is not enough to calculate either the molar mass or the molecular formula. So, since now you can discard options b. and c.
Telling that it is a hydrocarbon (option e.) is true but very vague compared with finding the empirical formula. So, you can also discard the option e.
The fact that the product has a triple bond cannot be concluded from the percent composition, you should find the molecular formula to assert whether it contains or not a triple bond. So, you could discard option a., which lets you only with choice d.
Let us find the empirical formula to be certain that it is CH₂.
1. <u>First, assume a basis of 100 g of compound</u>:
- H: 14.5% × 100 g = 14.0 g
- C: 85.5% × 100 g = 85.5 g
2. <u>Divide each element by its atomic mass to find number of moles</u>:
- H: 14.0 g / 1.008 g/mol = 14.38 mol
- C: 85.5 g / 12.011 g/mol = 7.12 mol
3. <u>Divide both amounts by the smallest number, to find the mole ratio</u>:
- H: 14.38 mol / 7.12 mol ≈ 2
- C: 7.12 mol / 7.12 mol = 1.
Hence, the ratio is 2:1 and the empirical formula is CH₂.
Answer:
- 10.555 kJ/mol.
Explanation:
∵ ∆G°rxn = ∆H°rxn - T∆S°rxn.
Where, ∆G°rxn is the standard free energy change of the reaction (J/mol).
∆H°rxn is the standard enthalpy change of the reaction (J/mol).
T is the temperature of the reaction (K).
∆S°rxn is the standard entorpy change of the reaction (J/mol.K).
∵ ∆H°rxn = ∑∆H°products - ∑∆H°reactants
<em>∴ ∆H°rxn = (2 x ∆H°f NOCl) - (1 x ∆H°f Cl₂) - (2 x ∆H°f NO) </em>= (2 x 51.71 kJ/mol) - (1 x 0) - (2 x 90.29 kJ/mol) = - 77.16 kJ/mol.
∵ ∆S°rxn = ∑∆S°products - ∑∆S°reactants
<em>∴ ∆S°rxn = (2 x ∆S° NOCl) - (1 x ∆S° Cl₂) - (2 x ∆S° NO) </em>= (2 x 261.6 J/mol.K) - (1 x 223.0 J/mol.K) - (2 x 210.65 J/mol.K) =<em> - 121.1 J/mol.K. = - 0.1211 kJ/mol.K.</em>
<em></em>
∵ ∆G°rxn = ∆H°rxn - T∆S°rxn.
<em>∴ ∆G°rxn = ∆H°rxn - T∆S°rxn </em>= (- 77.16 kJ/mol) - (550 K)(- 0.1211 kJ/mol.K) = <em>- 10.555 kJ/mol.</em>
Silver is Ag from the latin Argentum
Lead is Pb from the latin Plumbum
Answer:
C is correct
Explanation: Heat describes the transfer of thermal energy between molecules within a system and is measured in Joules. Heat measures how energy moves or flows. ... Temperature describes the average kinetic energy of molecules within a material or system and is measured in Celsius (°C), Kelvin(K), Fahrenheit (°F), or Rankine (R)
Answer:
Kim kim kim kim kim ath marath enthe kantha
Explanation:
Ninn chumbenem enne thellerthii.
Nin vadabell enne shwasichu!
