The question is incomplete, the complete question is;
In a laboratory experiment, students synthesized a new compound and found that when 12.23 grams of the compound were dissolved to make 228.1 mL of a benzene solution, the osmotic pressure generated was 4.55 atm at 298 K. The compound was also found to be non-volatile and a non-electrolyte. What is the molecular weight they determined for this compound?
Answer:
287.76 g/mol
Explanation:
From;
π
=
M
R
T
M = molarity
R= gas constant
T = temperature
number of moles = π * volume/RT
number of moles = 4.55 * 228.1/1000/0.082 * 298
number of moles = 1.037855/24.436
number of moles = 0.0425 moles
Molar mass = mass/number of moles
Molar mass = 12.23 grams/0.0425 moles
Molar mass = 287.76 g/mol
Salutations!
A kind of sedimentary rock formed from plant material over a long period of time is __________.
<span>A kind of sedimentary rock formed from plant material over a long period of time is coal. Coal is a fossil fuel as well.
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Have a great day!
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Answer: Option (b) is the correct answer.
Explanation:
A change that does not lead to any difference in chemical composition of a substance is known as a physical change.
For example, shape, size, mass, volume, density, boiling point, etc of a substance are all physical properties.
Boiling of water is a physical change as it leads to conversion of liquid state of water into vapor state.
On the other hand, changes that lead to bring change in chemical composition of a substance is known as a chemical change.
For example, exploding dynamite, rotting cheese etc are all chemical changes.
Thus, we can conclude that the statement no, boiling water is a physical change is true when water is heated, bubbles form in the water. This evidence is not of a chemical reaction.
Answer:
False hypermagnesaemia
Explanation:
Magnesium is predominantly an intracellular divalent action and it is important for optimal cellular function. It is an essential cofactor to many enzymes as well as being important for membrane function.
The body contain about 1 mol (approximately 25g) of magnesium.
Hemolyzed specimen will result in release of magnesium from intracellular to extracellular, causing elevation of the blood level of magnesium. This is a false hypermagnesaemia because it doesn't represent the real blood level.