The molality of a solute is equal to the moles of solute per kg of solvent. We are given the mole fraction of I₂ in CH₂Cl₂ is <em>X</em> = 0.115. If we can an arbitrary sample of 1 mole of solution, we will have:
0.115 mol I₂
1 - 0.115 = 0.885 mol CH₂Cl₂
We need moles of solute, which we have, and must convert our moles of solvent to kg:
0.885 mol x 84.93 g/mol = 75.2 g CH₂Cl₂ x 1 kg/1000g = 0.0752 kg CH₂Cl₂
We can now calculate the molality:
m = 0.115 mol I₂/0.0752 kg CH₂Cl₂
m = 1.53 mol I₂/kg CH₂Cl₂
The molality of the iodine solution is 1.53.
Rocks are made up deposited minerals that form and condense into rocks
Answer:
A) 20
B) 40
C) Ca
D) 10
E) 9
F) F
Explanation:
The MASS NUMBER is the number of protons + the number of neutrons.
The ATOMIC NUMBER is the number of protons.
You can take the MASS NUMBER - ATOMIC NUMBER = NUMBER OF NEUTRONS.
Each element is unique and distinguished by the NUMBER OF PROTONS = ATOMIC NUMBER, ie...the number of protons in its nucleus. You can find the element's name and symbol on the Periodic Table.
Answer:
No
Explanation:
The mass fraction is defined as:
where:
- wi: mass fraction of the substance i
- mi: mass of the substance i
- mt: total mass of the system
<u><em>The mass fraction of two substances (A and B), will be the same, ONLY if the mass of the substance A (mA) is the same as the mass of the substance B (mB).</em></u>
An equimolar mixutre of O2 and N2 has the same amount of moles of oxygen and nitrogen, just to give an example let's say that the system has 1 mole of O2 and 1 mole of N2. Then using the molecuar weigth of each of them we can calculate the mass:
mA= 1 mole of O2 * 16 g/1mol = 16 g
mB=1 mole of N2 *28 g/1mol=28 g
As mA≠mB then the mass fractions are not equal, so the answear is NO.
