Answer
Dmitri Mendeleev Explanation:The modern periodic tables is credited primarily to the russian chemist Dmitri Mendeleev. Mendeleev's table is based on the periodic law, which states that when elements are arranged in order of increasing mass, their properties recur periodically.
The freezing point of pure benzene (C₆H₆) is 5. 49 °C. The freezing point of a solution made using toluene (C₇H₈) in benzene is determined to be -13. 0 °C. What is the molality of the toluene? (Kf benzene = 5. 12 °C/m)
The molality of the toluene is 1.46 mol/kg.
What is molality?The molality of a solution is its molal concentration. Molal concentration is denoted by m. It is the mol of solute dissolves in 1 Kg solvent.
The depression at freezing point is directly proportional to the molality of the solution. The equation we use for this type of problem is:
ΔT=iKm [tex]f_m[/tex]
Where, ΔT [tex]f_m[/tex] is depression at freezing point, i is Van't hoff factor, m is molality and [tex]K_f[/tex] is the freezing point depression constant.
Toluene is a non-electrolyte and so the value of i for this is 1.
Depression at a freezing point is given as -13.[tex]0^0[/tex] and the [tex]K_f[/tex] is given as 5.12. So, we could calculate the molality of the solution using the equation written above.
Let's plug in the values in the equation:
ΔT=iKm[tex]f_m[/tex]
-7.51 =1 x5. 12 xm
m = [tex]\frac{7.51}{5. 12}[/tex]
m = 1.46 m
It means the molality of the solution is 1.46 mol/kg.
Hence, the molality of the solution is 1.46 mol/kg.
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Are two atoms of the same element identical?
Answer:
No It is not
Two of the same atoms are most likely not identical
Hi! I'm hoping someone can help me with this please thank you XD
The volume of a gas is 204mL when the pressure is 925kPa. At constant temperature, what's the final pressure if the volume increases to 306ml
Answer:
I don't know that anwser sorry
Determine from the balanced chemical reaction if
the derived mole ratio is correct or incorrect.
2 FeBr3 + 3Na2S → Fe2S3 + 6NaBr
1 moles NaBr
1 moles Nas
Answer:
Explanation:
It's not 1:1 as the ratio implies
There's a 6 in front of the NaBr
There's a 3 in front of the Na2S
Arguement
The ratio is (6 NaBr // 3 Na2S}
Answer
The ratio is {2 NaBr:: 1 Na2S}
Which term describes this change?
deposition
evaporation
melting
sublimation
-
1. N2 + 3H2 → 2NH3
If you form 5.24 moles of NH3 from the above reaction, how many moles of N2 were
present at the start of the reaction?
Answer: 2.62 moles
Explanation:
For every 2 moles of ammonia that are produced, 1 mole of nitrogen is consumed.
This means that if 5.24 moles of ammonia are produced, 5.24/2=2.62 moles of nitrogen are consumed.
(Word equation) which of the four metals - aluminium, copper, lead and silver is the most reactive
Answer:
Aluminum
Explanation:
I just used the Reactivity Series chart :)
compare and contrast then 4 types of friction?
Answer:
There are four types of friction: static, sliding, rolling, and fluid friction. Static, sliding, and rolling friction occur between solid surfaces. Static friction is strongest, followed by sliding
Explanation:
hope i help!.
In a thermonuclear device, the volume is 0.05L of gas and a pressure
of 4.0x106 atm. When the bomb goes off, it relases a gas into the
atmosphere at 1.0 atm, what is the volume of the gas after the
explosion?
Answer:
2 x 10^5 liters
Explanation:
P1V1 = P2 V2
P1V1 / P2 = V2 = .05 *4 x 10^6 / 1 = .2 x 10^6 liters
what is the industrial application of nitrogen monoxide
Answer:
it can be in the production of nitric acid
Answer:
Explanation:
Nitrogen oxides are used in the production of nitric acid, lacquers, dyes, and other chemicals. Nitrogen oxides are also used in rocket fuels, nitration of organic chemicals, and the manufacture of explosives.
What is the difference between natural and artificial radioactivity?
What is the difference between natural and artificial radioactivity?
Natural radioactivity comes from elements in nature. Artificial radioactivity comes from elements created in nuclear reactors and accelerators.
Answer:
natural is made from grass and artificial is made from toxic gas
Explanation:
yes
A sample of gas has an initial volume of 3.62 L at a pressure of 0.987 atm. If the volume of the gas decreases to 2.50 L, what will the pressure be
Answer: 1.43 atm
Explanation:
What splits into carbon and oxygen atoms
Part D
Calculate the following for test tube 1 and for test tube 2, and record the results in the table:
the number of moles of copper(II) sulfate used (Use 159.60 grams/mole as the molar mass of copper(II) sulfate.)
the heat absorbed by the water, in joules (Use Q = mCΔT, where 10.0 milliliters of water has a mass of 10.0 grams. Use 4.186 joules/gram degree Celsius as water’s specific heat capacity.)
the change in internal energy of the copper(II) sulfate (Assume that the energy released by the copper(II) sulfate is absorbed by the water.)
the reaction enthalpy, in joules/mole
The heat lost by copper(ii) sulfate is equal to heat absorbed by water since the total energy in the system remains constant according to the law of conservation of energy.
How can the number of moles be determined?The number of moles of a substance is determined using the formula below:
Number of moles = mass/molar massAssuming the mass of copper(ii) sulfate used is Mc, number of moles of copper(ii) sulfate used is:
Moles of copper(ii) sulfate = Mc/159.60 molesThe heat absorbed by water is calculated using the formula below:
Quantity of Heat, H = mass × specific heat capacity × temperature changemass of water = 10 g
Let temperature change be Tc
Heat absorbed by water = 10 × 4.186 × Tc = 41
86Tc
The change in internal energy, ΔU of copper(ii) sulfate, is given as:
ΔU = Q − Wwhere:
Q = heat absorbed by water
W = work done by or on the system
The enthalpy of the reaction is given as:
ΔH= energy released or absorbed/moles of copper (ii) sulfateTherefore, according to the law of conservation of energy, the total energy in the system remains constant.
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A video-disc player that is not playing still uses 6.0 W of power. What is the
current into the video-disc player if it is plugged into a standard 120-V outlet?
Answer: 0.05 A
Explanation:
Hope this helps!
A video-disc player that is not playing still uses 6.0 W of power. The current is 0.05 A.
What is Power?
The quantity of energy moved or converted per unit of time is known as power in physics. The watt, or one joule per second, is the unit of power in the International System of Units. Power is also referred to as activity in ancient writings. A scalar quantity is power.
Power is related to other factors; for instance, the power required to move a ground vehicle is equal to the product of the vehicle's velocity, traction force on its wheels, and aerodynamic drag.
A motor's output power is calculated by multiplying its torque output by the angular velocity of its output shaft. Similar to how the power expended in an electrical component of a circuit is the result of the current.
Therefore, A video-disc player that is not playing still uses 6.0 W of power. The current is 0.05 A.
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Ge (g) + 2Cl2 (g) <-> GeCl4 (g)
The value of the equilibrium constant for the reaction represented above is 1 x 10^10. What is the value of the equilibrium constant for the following reaction?
2GeCl4(g) = 2Ge(g) + 4Cl2 (g)
The equilibrium constant gives us an idea of the extent of reaction. For the reaction; 2GeCl4(g) = 2Ge(g) + 4Cl2 (g), the equilibrium constant is 1 * 10^-20.
What is equilibrium constant?The equilibrium constant gives us an idea of the extent of the conversion of reactants to products in a reaction.
In this case, we know that 2GeCl4(g) = 2Ge(g) + 4Cl2 (g) is the reverse of Ge (g) + 2Cl2 (g) <-> GeCl4 (g) hence we only need to invert the value of the equilibrium constant and raise it to power 2 to have 1 * 10^-20.
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How many molecules are there in 11.00 moles of carbon dioxide, CO2?
Answer:
Moles= 11/44 = 0.25 molesof CO2. Click to see full answer Considering this, how many moles of carbon are in 1 mole of co2? A mole of CO2molecules (we usually just say “a mole of CO2”) has one moleof carbonatoms and two molesof oxygen atoms.
Exxplanation:
What is the molar mass of Ca(NO3)2?
102. 2 g/mol
134. 1 g/mol
164. 1 g/mol
204. 2 g/mol
Answer:
The answer is 164.1 g/mol
Explanation:
The heat capacity of an object depends in part on its__
Answer:
It depends on its mass and its chemical composition. Give me Brainiliest
What will be the ratio of the mean free path of the air molecules at 80 °c to their mean free path at stp?.
Answer:
1.00
Explanation:
I honestly have no idea. I found this online and apparently it was correct. I thought at first I would use d = RT/(Nₐ * P *π (2r)². Since all values besides T are constant, I thought the ratio would just be (273+80)/273 since 273 is standard temperature in Kelvin. However, I think the answer is 1.00 since the pressure would also increase since it is a rigid container, effectively cancelling out the increase in temperature.
The ratio of the mean free path of air molecules at 80 °C to their mean free path at STP is approximately 0.934.
What is mean free path?The mean free path (MFP) of gas molecules is the average distance they travel between collisions with other molecules. It depends on the temperature, pressure, and molecular size of the gas. The MFP of air molecules at standard temperature and pressure (STP) is about 68 nanometers.
To find the ratio of the mean free path of air molecules at 80 °C to their mean free path at STP, we need to use the following formula:
Ratio = (MFP at 80 °C) / (MFP at STP)
The MFP at 80 °C can be calculated using the kinetic theory of gases, which states that:
MFP = (k × T) / (sqrt(2) × pi × d² × P)
where k is Boltzmann's constant, T is the temperature in Kelvin, d is the molecular diameter, and P is the pressure.
For air molecules, d is about 0.364 nanometers. At 80 °C (353 K), the pressure of air is about 101.3 kPa. Plugging these values into the formula, we get:
MFP at 80 °C = (1.38 × 10⁻²³ J/K ×353 K) / (sqrt(2) × 3.14 ×(0.364 × 10⁻⁹m)² ×101.3 × 10³ Pa)
MFP at 80 °C = 63.5 nanometers
Now we can calculate the ratio:
ratio = (MFP at 80 °C) / (MFP at STP)
ratio = 63.5 nm / 68 nm
ratio ≈ 0.934
Therefore, the ratio of the mean free path of air molecules at 80 °C to their mean free path at STP is approximately 0.934.
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Is water solvent or solute
Answer:
Water is a solvent.
Explanation:
What is solvent? Solvent is substance, ordinarily a liquid, in which other materials dissolve to form a solution.
When warm air is forced upward
along a cold front, what might
happen?
A. A thunderstorm can form.
B. A hurricane can form.
C. A dry spell occurs.
D. Clear sky appears.
Answer:
A. A thunderstorm can form.
Explanation:
When it meets warmer air a cold front forms and clouds will appear as the warm air rises and then cools. This may lead to heavy rain along the cold front.
If I have 22,9 moles of a gas at a pressure of 12.4 atm and a volume of 24 liters, what is the temperature?
Answer:
160 K, using 2 SF,
Explanation:
Ideal Gas law, rearrange to solve for T (K), answer about 158.3 round to 2SF
PV = nRT
Given that E
o
= 0. 52 V for the reduction Cu+(aq) + e− → Cu(s), calculate E
o
, ΔG
o
, and K for the following reaction at 25°C:
2Cu+(aq) ⇌ Cu2+(aq) + Cu(s)
The equilibrium constant of the reaction is 1.21 * 10^6 while the change in free energy is -34.7 kJ.
What is equilirium constant?The equilibrium constant shows the extent of conversion of reactants to products.
Now we know from the Nernst equation that;
Ecell = E°cell - 0.0592/n logQ
E°cell = 0.52−0.16=0.36 V
Since Ecell = 0 V at equilibrium,
0 = 0.36 - 0.0592/1 log K
0.36 = 0.0592/1 log K
log K = 0.36/ 0.0592
K = antiog (0.36/ 0.0592)
K = 1.21 * 10^6
ΔG = -RT lnK
ΔG =-(8.314 * 298 * ln1.21 * 10^6)
ΔG =-34.7 kJ
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Giving brainliest, please HELP!
Answer:
Third choice
Explanation:
From the graph.....more heat is required to change from Liquid to a gas than is required to change from a solid to a liquid ( see how the flat line portion is longer?)
Help please will give 20 points.Which stage of metamorphosis starts when a caterpillar egg hatches? a Adult b Larva c Nymph d Pupa
Answer:
The answer is B a larva
Explanation:
Answer:
B. Larva
Explanation:
it is when a catipliar hatches
Help I Will Mark Brainlist !! (ATTACHED IMAGE BELOW) Which of the diagrams below would be the FASTEST? _____ Why? Which of the diagrams below would be the SLOWEST? ____ Why?
Answer:
Fastest C. Reaction time is faster
Slowest A. Reaction time is slower and it takes longer to finish
Explanation:
Which is composed of aromatic hydrocarbons?
An example of The substance which is composed of aromatic hydrocarbins is : Pain reliever.
Aromatic hydrocarbonsAromatic hydrocarbons are hydrocarbons in nature are composed of 6 rings of carbn atoms ( fused benzene rings ) certain compounds like petroluem contain aromatic hydrocarbons in nature. Certain medical drugs administered are composed of aromatic hydrocarbins an example of such drugs are pain relievers.
Hence we can conclude that the substance which is composed of aromatic hydrocarbons is pain reiever.
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A 33.6 mL solution of KCl has a mass of 27.29 g. After evaporating to dryness, the dry salt residues has a mass of 6.31 g. Calculate the following: a. %m/m b. Molarity (M)
For the molarity and the percentage of the mass of kcl are mathematically given as
%m/m = 23.1%, molarity = 3.38M
What is the molarity?
Generally, the equation for the percentage of the mass of kcl is mathematically given as
(mass of kcl/mass of solution)x 100
therefore
%m/m = (6.31/27.29)x100
%m/m = 23.1%
The molarity
(no of mol/ vol of sol)
molarity = 0.0846mol/0.0250 L
molarity = 3.38M
In conclusion, the molarity is given as
molarity = 3.38M
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Some calcifiers can use bicarbonate (HCO3-) to make their shells. How will they be affected by the decrease in pH
The removal of this ion from water by the calcifiers will definitely decrease the pH of water.
What is the bicarbonate ion?The bicarbonate ion is the ion that is designated as HCO3-. We must notice that this ion is present in abundant amounts in the sea. This amount definitely make the sea slightly alkaline.
Now we must note that the removal of this ion from water by the calcifiers that require it to make their shell will definitely decrease the pH of water.
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