I am in desperate need of help will give 40 points to whoever helps me!!!!! I have a quiz tomorrow but I have no idea how to do these practice problems. I know u have to use the boiling and freezing pint formula but i don't know how to plug them in because these problems all look different and asks for different things
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Freezing point depression or Boiling point elevation:
ΔT = -K (m) (i)
ΔT is the change in the freezing point or the boiling point not the freezing point/boiling point. Therefore, it should be added to the original value of the property of the solvent.
K is a constant called the molal freezing point depression constant and for the boiling point is the boiling point elevation constant. It is a property of the solvent.
m is the concentration of the solute in the solvent in terms of molality or kg solute/kg solvent.
i is the vant hoff factor which will represent the number of ions which the solute dissociates when in solution.
Related Questions
Propanone is more soluble in water compared to propane mainly because propanone?
the trend for ionization energy is a general increase from left to right across a period. However phosphorus is found to have higher first ionization energy value than sulfur. Explain this exception to the general trend in terms of electron arrangements and attraction/repulsion
A lahar is a type of mudflow that occurs
Which of the following types of organelles are most important in providing a cell with energy
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The correct option for above statement is:
B.Joseph Proust
Explanation:
Joseph Proust printed his Law of Definite Proportions (or Law of Constant Composition) in 1794. This law states that a compound consists of exact proportions of parts by mass no matter however the compound was created.
2) less mass and less penetrating power
3) more mass and greater penetrating power
4)more mass and less penetrating power
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An alpha particle has more than 7000 times the mass a beta, but it has less penetrating power because it has a shorter range.
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I hope this helps. Let me know if anything is unclear.
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1) Assume 100 g sample
63.15% C * 100 g = 63.15g
5.30% H * 100 g = 5.30g
31.55% O * 100g = 31.55g
2) Convert mass to moles using their atomic weights
63.15 g * 1 mol C / 12.0107 g C = 5.2870 mol C
5.30 g * 1mol H / 1.0079 g H = 5.2585 mol H
31.55 g * 1mol O / 15.9994 O = 1.9719 mol O
3) Divide each quantity by the smallest number of moles
5.2870 mol C / 1.9719 mol = 2.6812 C = 2 C
5.2584 mol H / 1.9719 mol = 2.6667 H = 2 H
1.9719 mol O / 1.9719 mol = 1.000 O = 1 O
Empirical Formula is C₂H₂O
If the problem is silent, the molecular weight is equivalent to the empirical weight.
To get the molecular formula, divide the molecular weight by the empirical weight to get the multiple.
Molecular Weight is not mentioned thus it is equivalent to Empirical Weight which is:
Atom Number in Molecule Atomic Weight Total Mass
C 2 12.0107 24.0214
H 2 1.0079 2.0158
O 1 15.9994 15.9994
Total weight is 42.0366
Molecular weight / Empirical Weight = Multiple to be multiplied to the Empirical Formula
42.0366 / 42.0366 = 1
Molecular Formula isC₂H₂O
(2) electrons and protons
(3) neutrons and protons
(4) neutrons, protons, and electrons
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The nucleus of an atom contains the majority of its mass and is composed of two types of subatomic particles: protons and neutrons.
1. Protons: Protons are positively charged particles found in the nucleus of an atom. Each proton carries a charge of +1 and has a relatively high mass compared to electrons. The number of protons in an atom's nucleus determines its atomic number, which in turn defines the element. In the case of helium-4 (He-4), it has an atomic number of 2, indicating that there are two protons in its nucleus.
2. Neutrons: Neutrons are electrically neutral particles, meaning they have no net charge. They are also located in the nucleus of an atom. Neutrons contribute to the mass of the nucleus and help stabilize it by balancing the electrostatic repulsion between positively charged protons. Helium-4, being a stable isotope of helium, has two neutrons in its nucleus, along with the two protons.
Electrons, on the other hand, are found in electron shells or orbitals outside the nucleus, not within it. Their role is to move around the nucleus and create the electron cloud or electron configuration, which determines an atom's chemical properties.
In summary, the nucleus of a helium-4 atom consists of neutrons and protons, making option (3) "neutrons and protons" the correct choice. Electrons, which are negatively charged, are located outside the nucleus and are involved in chemical interactions and bonding.
Learn more about subatomic here:
#SPJ6
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the science or practice of farming, including cultivation of the soil for the growing of crops and the rearing of animals to provide food, wool, and other products.
Answer:
the science or practice of farming, including cultivation of the soil for the growing of crops and the rearing of animals to provide food, wool, and other products.