Answer:
Explanation:
For a flower to appear blue, "it needs to be able to produce a molecule that can absorb very small amounts of energy," in order to absorb the red part of the spectrum, Kupferschmidt said.
Answer:
Mass = 0.32 g
Explanation:
Given data:
Mass of CH₄ = ?
Volume of CH₄ = 500 mL (500 mL× 1L/1000 mL= 0.5 L)
Temperature = 273 K
Pressure = 1 atm
Solution:
Volume of CH₄:
500 mL (500 mL× 1L/1000 mL= 0.5 L)
The given problem will be solve by using general gas equation,
PV = nRT
P= Pressure
V = volume
n = number of moles
R = general gas constant = 0.0821 atm.L/ mol.K
T = temperature in kelvin
By putting values,
1 atm× 0.5 L = n×0.0821 atm.L/ mol.K × 273 K
0.5 atm.L = n×22.4 atm.L/ mol
n = 0.5 atm.L / 22.4 atm.L/ mol
n = 0.02 mol
Mass in gram:
Mass = number of moles × molar mass
Mass = 0.02 mol × 16 g/mol
Mass = 0.32 g
Answer: 72.4 kJ/mol
Explanation:
The balanced chemical reaction is,

The expression for enthalpy change is,
![\Delta H=\sum [n\times \Delta H_f(product)]-\sum [n\times \Delta H_f(reactant)]](https://tex.z-dn.net/?f=%5CDelta%20H%3D%5Csum%20%5Bn%5Ctimes%20%5CDelta%20H_f%28product%29%5D-%5Csum%20%5Bn%5Ctimes%20%5CDelta%20H_f%28reactant%29%5D)
![\Delta H=[(n_{CO_2}\times \Delta H_{CO_2})+(n_{H_2O}\times \Delta H_{H_2O})]-[(n_{O_2}\times \Delta H_{O_2})+(n_{C_3H_8}\times \Delta H_{C_3H_8})]](https://tex.z-dn.net/?f=%5CDelta%20H%3D%5B%28n_%7BCO_2%7D%5Ctimes%20%5CDelta%20H_%7BCO_2%7D%29%2B%28n_%7BH_2O%7D%5Ctimes%20%5CDelta%20H_%7BH_2O%7D%29%5D-%5B%28n_%7BO_2%7D%5Ctimes%20%5CDelta%20H_%7BO_2%7D%29%2B%28n_%7BC_3H_8%7D%5Ctimes%20%5CDelta%20H_%7BC_3H_8%7D%29%5D)
where,
n = number of moles
(as heat of formation of substances in their standard state is zero
Now put all the given values in this expression, we get
![-2220.1=[(3\times -393.5)+(4\times -241.8)]-[(5\times 0)+(1\times \Delta H_{C_3H_8})]](https://tex.z-dn.net/?f=-2220.1%3D%5B%283%5Ctimes%20-393.5%29%2B%284%5Ctimes%20-241.8%29%5D-%5B%285%5Ctimes%200%29%2B%281%5Ctimes%20%5CDelta%20H_%7BC_3H_8%7D%29%5D)

Therefore, the heat of formation of propane is 72.4 kJ/mol
Hi,
An ion with unequal number of protons and electrons haves a name. A name depends on whether there are more protons than electrons (CATION) or if there are more electrons than protons (ANION).
Hope this helps.
r3t40