Missing question: Z:X = 7:1 A:Z = 2.5:1 A:Z = 2.2:1 Y:X = 11:1.
Answer is:<span> Z:X = 7:1 and Y:X = 11:1.
Law of multiple proportions or Dalton's Law
said that the ratios of the masses of the second element which
combine with a fixed mass of the first element will be ratios of small whole
numbers.
In this example ratios are whole numbers, A:Z = 2.5 : 1
and A:Z = 2.2 : 1 are not whole number ratios.</span>
Answer:
a=28600J; b=90.6 J/K; c=402 torr
Explanation:
(a) considering the data given
Vapour pressure P1 =0 at Temperature T1 = 42.43˚C,
Vapour pressure P2 = 273.15 at Temperature T2= 315.58 K)
Using the Clausius-Clapeyron Equation
ln (P2/P1) = (ΔH/R)(1/T2 - 1/T1)
In 760/140 = ΔH/8.314 J/mol/K × (1/315.58K -- 1/273.15K)
ΔH vap= +28.6 kJ/mol or 28600J
(b) using the Equation ΔG°=ΔH° - TΔS to solve forΔS.
Since ΔG at boiling point is zero,
ΔS =(ΔH°vap/Τb)
ΔS = 28600 J/315.58 K
= 90.6 J/K
(c) using ln (P2/P1) = (ΔH/R)(1/T2 - 1/T1)
ln P298 K/1 atm = 28600 J/8.314 J/mol/K × (1/298.15K - 1/315.58K)
P298 K = 0.529 atm
= 402 torr
Topsoil because plants and decaying animals add more humus to the soil
Answer:
- Please, find the drawing in the picture attached.
Explanation:
A simple model or drawing of the structure of an atom may be performed showing the electrons on the different energy levels (shells), plus the nucleons (protons and neutrons).
Then, you need the information on:
- number of protons (atomic number)
- electron configuration
- number of neutrons
The first step is to find the atomic number of the atom. You find that information in the periodic table, where the elements are show with their chemical symbol.
The chemical symbol of sodium is Na. It is located in the group (colum) 1 and period (raw) 3. There you find that the atomic number is 11. Hence your drawing must show 11 protons.
Since the atom is neutral, the number of electrons is also 11. So, you must place the electrons in the following energy levels or shells:
Main energy level shell number of electrons
n = 1 K 2 (this is the maximum in this level)
n= 2 L 8 (this is the maximun in this level)
n= 3 M 1 (the maximum in this level is 18)
Now that you have the number of protons and the location of the electrons, you must determine the number of neutrons.
In the periodict table you will also find the atomic mass of the elements. The atomic mass of sodium is 22.990 amu. That means that most sodium atoms have mass number (number of protons plus neutrons) 23. Some isotopes will have less neutrons, but you can draw your model using the most typical isotope with 23 nucleons. This means, that the number of neutrons is 23 nucleons - 11 protons = 12 neutrons.
The law of conservation of mass states that mass can neither be created or destroyed in a chemical reaction.