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Related Questions
The Heat of vaporization for NH3= 1360 J/g. Calculate the quantity of heat energy (in kJ)needed to completely boil a 155 gram sample at its boiling pointgeneral formula
How did Mendeleev come up with the first periodic table of the elements? (1 point)A He determined the mass of atoms of each element.B He estimated the number of electrons in atoms of each element.C He arranged the elements by different properties to find a pattern.D He organized the elements by their atomic number.
A 6.13 g sample of an unknown salt (MM = 116.82g/mol) is dissolved in 150.00 g water in a coffee cupcalorimeter. Before placing the sample in the water, thetemperature of the salt and water is 23.72°C. After thesalt has completely dissolved, the temperature of thesolution is 28.54°C.If 3.15 x 10J of heat was gained by the solution, whatis the total heat for the dissolution reaction of the 6.13 gof salt?
Jesim wants to help Nancy understand the movement that happens during one Earth year, Jassim holds a small globe representing Earth, and Nancy holds a large ball representing the Sun. What should Jessim do to showNancy what happens during one Earth year?Jessim should not move except to slowly spin the globeJesim should slowly spin the globe and walk away from NancyJessim should have Nancy walk around him while spinning the ballJessim should spin the globe quickly while walking in a circle around Nancy
B. Salt water has too few water molecules and too many salt molecules.
O
C. Salt water contains molecules that are poisonous to humans.
O
D. Salt water contains molecules that are too large for humans to process.
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Answer:
B. Salt water has too few water molecules and too many salt molecules
Explanation:
Seawater is toxic to humans because your body is unable to get rid of the salt that comes from seawater. Your body normally gets rid of excess salt by having the kidneys produce urine, but it needs freshwater to dilute the salt in your body for the kidneys to work properly.
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The question is incomplete, complete question is ;
A deep-sea diver uses a gas cylinder with a volume of 10.0 L and a content of 51.8 g of and 33.1 g of He. Calculate the partial pressure of each gas and the total pressure if the temperature of the gas is 21°C.Express the pressures in atmospheres to three significant digits separated by commas.
Answer:
Partial pressure of the oxygen gas is 3.91 atm.
Partial pressure of the helium gas is 20.0 atm
Total pressure of the gases is 24.0 atm
Explanation:
Moles of oxygen gas =
Moles of helium gas =
Total moles of gas =
Volume of the cylinder = V = 10.0 L
Total pressure in the cylinder = P = ?
Temperature of the gas in cylinder = T = 21°C = 21 + 273 K = 294 K
PV = nRT ( ideal gas equation )
P = 23.88 atm ≈ 23.9
Partial pressure of the individual gas will be determined by the help of Dalton's law:
partial pressure = Total pressure × mole fraction of gas
Partial pressure of the oxygen gas
Partial pressure of the helium gas
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Answer:
The freezing point of a solution is lowered compared to the freezing point of the pure solvent. The amount of depression of the freezing point is proportional to the molality of the solute. The greater the molality of a solution, the lower its freezing point. To compare the freezing points of these solutions, we need to determine which one has the highest molality.
First, we need to determine the number of particles that each solute will produce in solution, as this affects the amount of depression of the freezing point.
KNO3 dissociates into two ions: K+ and NO3-, so it will produce two particles per formula unit.
BaCl2 dissociates into three ions: Ba2+ and two Cl-, so it will produce three particles per formula unit.
Ethylene glycol does not dissociate in solution, so it will produce one particle per molecule.
Na3PO4 dissociates into four ions: three Na+ and one PO43-, so it will produce four particles per formula unit.
Now, we can calculate the molality (moles of solute per kilogram of solvent) for each solution:
For 0.10 m KNO3: molality = 0.10 mol / 1 kg = 0.10 m
For 0.10 m BaCl2: molality = 0.10 mol x 3 particles / 1 kg = 0.30 m
For 0.10 m ethylene glycol: molality = 0.10 mol / 1 kg = 0.10 m
For 0.10 m Na3PO4: molality = 0.10 mol x 4 particles / 1 kg = 0.40 m
So, the solutions in order of decreasing freezing points are:
0.10 m Na3PO4 (highest molality)
0.10 m BaCl2
0.10 m KNO3 and 0.10 m ethylene glycol (same molality, but KNO3 has a smaller van't Hoff factor than ethylene glycol, so it will have a slightly higher freezing point)
Explanation:
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Answer:
0,12 μmol/L of MgF₂
Explanation:
Preparation of solutions is a common work in chemist's life.
In this porblem says that you measure 0,00598 μmol of MgF₂ in 50,0 mL of water and you must calculate concentration in μmol/L
You have 0,00598 μmol but not Liters.
To obtain liters you sholud convert mL to L, knowing 1000mL are 1 L, thus:
50,0 mL (1L/1000mL) = 0,05 L of water.
Thus, concentration in μmol/L is:
0,00598 μmol / 0,05 L = 0,12 μmol/L -The problem request answer with two significant digits-
I hope it helps!
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Answer:
-270.76°C
Explanation:
Given that metal Thallium becomes superconducting below the temperature of 2.39 kelvin i.e. this temperature is critical temperature for Thallium and below critical temperature a metal offers no resistance to the flow of electric current. Also the metal below its critical temperature expels the magnetic field in such a way that they do not penetrate the metal and pass through its surface only.
We have the relation between kelvin scale and degree Celsius scale of temperature measurement as:
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Answer:
False
Explanation:
"Observations is the action of observing something or someone carefully or in order to gain information" - google dictionary. This definition does not completely match the definition given, so the answer is false.
I hope this helps!
Answer: true
Explanation: the action or process of observing something or someone carefully or in order to gain information that is the real definition