Answer:
Explanation:
Nitrogen gas in nitrogen cylinder is in gaseous form only . So when gas is released , pressure decreases because moles of gas in the cylinder decreases .
Propane gas in cylinder is in liquified form . The gas is partially in gaseous and liquid form . So when gas is released outside , pressure decreases inside but due to low pressure , some liquid form is converted into gaseous form which restores the pressure of gas inside cylinder . Hence , the pressure of gas remains unchanged inside cylinder.
Wavelength= velocity/frequency
wavelength= (3.0 x 10^8m/s) / 7.5 x 10^12 Hz)
you can do the math
I am assuming u that 108 is 10^8 and the 1012 is 10^12
Answer:
Aromatic Hydrocarbons
Explanation:
Aromatic (Pleasant Odour) Hydrocarbons are those having pleasant odours.
Answer:
IO₂
Explanation:
We have been given the mass percentages of the elements that makes up the compound:
Mass percentage given are:
Iodine = 79.86%
Oxygen = 20.14%
To calculate the empirical formula which is the simplest formula of the compound, we follow these steps:
> Express the mass percentages as the mass of the elements of the compound.
> Find the number of moles by dividing through by the atomic masses
> Divide by the smallest and either approximate to nearest whole number or multiply through by a factor.
> The ratio is the empirical formula of the compound.
Solution:
I O
% of elements 79.86 20.14
Mass (in g) 79.86 20.14
Moles(divide by
Atomic mass) 79.86/127 20.14/16
Moles 0.634 1.259
Dividing by
Smallest 0.634/0.634 1.259/0.634
1 2
The empirical formula is IO₂
Given molecule Lithium iodide (LiI)
Heat of hydration = -793 kj/mol
Lattice energy = -730 kJ/mol
Heat of hydration = Heat of solution - Lattice energy
Heat of solution = Hydration + Lattice = -793 + (- 730) = -1523 kJ/mol
Now,
Mass of LiI = 15.0 g
molar mass of LiI = 134 g/mol
# moles of LiI = 15/134 = 0.112 moles
Heat of solution for 1 mole of LiI = -1523 KJ
Therefore, for 0.112 moles of LiI the corresponding heat is
= 0.112 *(-1532) = 171.6 kJ
