Answer:
A) the NaI solution will have a higher boiling point than the KI solution
Explanation:
We must have it behind our minds that the addition of a solute to water elevates the boiling point of water.
Boiling point elevation is a colligative property. It depends on the amount of solute present.
We know that;
ΔTb = Kb m i
Where;
ΔTb = boiling point elevation
Kb = boiling point constant
m = molality
i = Van't Hoff factor
Since KI and NaI has the same number of particles(two particles each), the boiling point elevation (ΔTb) depends on the molality of each solution. The molality also depends on the molar mass of each substance. The molality of NaI is greater than the molality of KI hence the boiling point NaI is greater than the boiling point of KI.
So;
200mL of water = 200g of water
Mass of solvent = 200g/1000 = 0.2 Kg
Molality of NaI = 5g/150 g/mol * 1/0.2 = 0.167 m
molality of KI = 5g/166 * 1/0.2 = 0.151 m
Kb for water = 0.512 oC m-1
Boiling point of water = 100 oC
Let the boiling point of NaI be A
A - 100 = 0.512 * 0.167 * 2
A = (0.512 * 0.167 * 2) + 100
A = 100.171 oC
Let the boiling point of KI be B
B - 100 = 0.512 * 0.151 * 2
B = (0.512 * 0.151 * 2) + 100
B = 100.154 oC
Hence;
Boiling point of NaI > Boiling point of KI
Calculate the decrease in temperature when 7.00 L at 21.5 °C is compressed to 4.00 L. The pressure remains constant at 101.3 kPa.
Explanation:
[tex] \frac{P _{1} V _{1} }{T _{2}} = \frac{P _{2} V _{2}}{T _{1}} \\ \frac{(101300 \times 7)}{(21.5 + 273)} = \frac{(101300 \times 4)}{T _{2}} \\ T _{2} = \frac{(405200 \times 294.5)}{(709100)} \\ T _{2} = 168.3 \: kelvin \\ decrease \: in \: temperature = (294.5 - 168.3) \\ = 126.2 \: kelvin[/tex]
What is the mass of 34.6 L of oxygen? How many molecules of oxygen are in 34.6 L of oxygen?
Answer:
49.4 grams; 9.29 x 10^23 molecules O2
Explanation:
In order to solve for the mass of oxygen, you first must find out how many moles of oxygen there are in 34.6 L.
There are 22.4 L in one mole of gas, so to get amount of moles, divide 34.6 by 22.4.
34.6 / 22.4 = 1.544 mol
In order to calculate mass, multiply the amount of moles by the molar mass of oxygen, which is in this case 32.00 g/mol.
1.544 * 32.00 = 49.4 grams
To calculate the amount of molecules, multiply the amount of moles by Avogadro's number, 6.02 x 10^23, which basically represents how many atoms/molecules there are in a mole of any substance.
1.544 * (6.02 x 10^23) = 9.29 x 10^23 molecules O2
Which is true for a substance that releases energy?
OA. The energy release decreases the molecular motion and the kinetic energy of the substance.
B. The energy release decreases the molecular motion but increases the kinetic energy of the substance.
C. The energy release increases the molecular motion and the kinetic energy of the substance.
D. The energy release increases the molecular motion but decreases the kinetic energy of the substance.
E. The energy release is used only to change the state of the substance.
A) 400 gramos de disolución al 6 % m/m. R: 24 g sto. Y 376 g ste. b) 56 gramos de disolución al 30 % m/m. R: 16,8 g y 39,2 g c) 450 gramos de disolución al 10 % m/m R: 45 g y 405 g d) 200 gramos de disolución al 5 % m/m R: 10 g y 190 g e) 450 gramos de disolución al 20 % v/v R: 90 mL y 360 mL f) 980 mL de disolución al 25 % v/v R: 245 mL y 735 mL. g) 50 mL de disolución al 30 % v/v R: 15 mL y 35 Ml
Answer:
A) 24g soluto y 376g solvente.
B) 16.8g soluto y 39.2g solvente
C) 45g soluto y 405g solvente
D) 10g soluto y 190g solvente
E) 90mL soluto y 360mL solvente
F) 245mL soluto y 735mL solvente
G) 15mL soluto y 35mL solvente
Explanation:
El porcentaje masa/masa (% m/m) se define como la masa de soluto presente en 100g de solución (Soluto + solvente).
De la misma manera, el porcentaje volumen/volumen se define como el volumen de soluto en 100mL de solución:
A) 400 gramos de disolución al 6 % m/m.
400g solución * (6g soluto / 100g solución) = 24g soluto
400g solución - 24g soluto = 376g solvente
b) 56 gramos de disolución al 30 % m/m.
56 gramos de disolución al 30% m/m.
56g solución * (30g soluto / 100g solución) = 16.8g soluto
56g solución - 16.8g soluto = 39.2g solvente
c) 450 gramos de disolución al 10 % m/m
450 gramos de disolución al 10% m/m.
450g solución * (10g soluto / 100g solución) = 45g soluto
450g solución - 45g soluto = 405g solvente
d) 200 gramos de disolución al 5 % m/m
200 gramos de disolución al 5% m/m.
200g solución * (5g soluto / 100g solución) = 10g soluto
200g solución - 10g soluto = 190g solvente
e) 450 mL de disolución al 20 % v/v
450 mL de disolución al 20% m/m.
450 mL * (20mL soluto / 100mL solución) = 90mL soluto
450mL solución - 90mL soluto = 360mL solvente
f) 980 mL de disolución al 25 % v/v
980 mL de disolución al 25% m/m.
980 mL * (25mL soluto / 100mL solución) = 245mL soluto
980mL solución - 245mL soluto = 735mL solvente
g) 50 mL de disolución al 30 % v/v
50 mL de disolución al 30% m/m.
50 mL * (30mL soluto / 100mL solución) = 15mL soluto
50mL solución - 15mL soluto = 35mL solvente
_S8+_O2=_SO2
please help balance
Answer:
S8+8o2 = 8so2
this is balance d
-Carbon and Oxygen combine to from carbon dioxide
Answer:
Carbon and oxygen combine to form two oxides, carbon monoxide and carbon dioxide in which the ratio of the weights of carbon and oxygen is respectively 12:16 and 12:32.
Which statement about hydrocarbons is FALSE?
a
The number one use of hydrocarbons is as a fuel
source.
b
Most hydrocarbons we use today come from
sustainable, renewable sources.
с
Hydrocarbons are useful in industries from
transportation to road work to cosmetics.
d
The bulk of hydrocarbons we use today were
formed hundreds of millions of years ago.
Answer:
b
Explanation:
Hydrocarbons provide 84% of the world's energy, but they are non-renewable. Hydrocarbons are the most economic form of energy.
The total pressure of an 02-Ar-He gas mixture is 755 mmHg. If the partial pressure of Ar is 174 mmHg
and the partial pressure of He is 389 mmHg,
then the partial pressure of 02 is what?
Please help i forgot how to do this
Answer:
2 significant figures
Explanation:
0.19312
0.19 or 0.2
what has changed in the atmosphere that give the rock strata the appearance of rust?(red/orange color).
Answer:
Explained below.
Explanation:
What has changed in the atmosphere is that oxidation has occurred where an oxidizing chemical specie has reacted with an oxygen containing compound.
Now these chemicals when they react with rain and fall on rocks react with the rocks to weaken them in a process known as chemical weathering.
Now when this weathering from the oxidizing chemicals from the rain react with rocks that contain iron, it leads to the rock having an appearance of rust.
Which of the following elements has the lowest electron affinity?
a. Si
b. F
c. Cl
d. K
Answer:
k
Explanation:
electron affinity (EA) depends on various factors like effective nuclear charge (enc) , size of the atom, ellipticity of sub-shell (ep) , nature of configuration.
more is the enc more will be the EA
more is the size less will be the EA
more valance shell ellipticity (closer to the nuclei) more will the EA ( all given element posses P orbital in the valance shell)
What is the major difference, in terms of weathering type, between Albany, NY and Washington, D.C.? What might explain this difference?
The breakdown or dissolution of rocks and minerals of the planet's surface is called weathering it can be chemical, biological or physical.
Chemical weathering occurs in regions with high rainfall and high temperature.
In Albany, NY the temperature is 9°C with 98 cm rainfall while in Washington, DC the temperature is 15°C with 111 cm rainfall that is Washington is hotter compared to Albany so it will have chemical weathering.Water (rainfall) and temperature is the main cause of weathering as they loosen and breaks the mineral of rock surfaces.The rocks and minerals get dissolved in the water bodies because of erosion by which they get carried in oceans.Therefore, Albany will have mechanical while Washington will suffer from chemical weathering.
To learn more about weathering types follow the link:
https://brainly.com/question/516958
Of the following which atom pairs will form covalent bonds
Answer:
si and p
o and F
Explanation:
covalent bonds are formed between non metals
1 cannot be accepted as Na is a metal
3 cannot be accepted as Ca is a metal
5 cannot be accepted as Mg is a metal
In sexual reproduction, if each chromosome in a pair has the same genes, how is genetic variety possible?
Answer:
The same genes or slightly different versions of the same gene can be found on each chromosome in a pair. They form a line and split off bits of themselves, which they barter with one another. In sexual reproduction, crossing over is the first method that genes are shuffled to develop genetic variation.
Name the planet: Until recently, this stormy, blue-colored planet had a great dark spot on it, which was a high pressure cyclone.
Answer:
Explanation:
THE PLANET NAME IS NEPTUNE
Circle the solution with the highest concentration
a. 5.0M
c. 0.6M
b. 1.0M
d. 0.75M
Answer:
answer is option a..............
Please help no links
Ms. Daly had Hydrogen gas that was cooled from 100 °C to 50.5°C. The new volume was 20 L. What was its original volume?
20.
50.
Answer:
23 L
Explanation:
We'll begin by converting celsius temperature to Kelvin temperature. This can be obtained as follow:
T(K) = T(°C) + 273
Initial temperature (T₁) = 100 °C
Initial temperature (T₁) = 100 °C + 273
Initial temperature (T₁) = 373 K
Final temperature (T₂) = 50.5 °C
Final temperature (T₂) = 50.5 °C + 273
Final temperature (T₂) = 323.5 K
Finally, we shall determine the initial volume of gas. This can be obtained as follow:
Initial temperature (T₁) = 373 K
Final temperature (T₂) = 323.5 K
Final volume (V₂) = 20 L
Initial volume (V₁) =?
V₁/T₁ = V₂/T₂
V₁ / 373 = 20 / 323.5
Cross multiply
V₁ × 323.5 = 373 × 20
V₁ × 323.5 = 7460
Divide both side by 323.5
V₁ = 7460 / 323.5
V₁ = 23 L
Thus, the original volume of the gas is 23 L
HELP ASAP PLEASE CHEMISTRY
The rate of reaction was measured during a chemical reaction. After the first 3 seconds, the rate of reaction was 1.8 x10−6 M/s. Which of the following would you expect after another 3 seconds?
The rate would be lower, and the concentration of products would be higher.
The rate would be lower, and the concentration of products would be lower.
The rate would be higher, and the concentration of products would be higher.
The rate would be higher, and the concentration of products would be lower.
Answer:
The rate would be higher, and the concentration of products would be lower.
Explanation:
The correct answer is The rate would be lower, and the concentration of products would be higher.
The rate of reaction refers to the speed with which reactants are converted into products.
The rate of reaction decreases as the reaction progresses because more reactants are being converted into products.
As such, the reactant concentration decreases and the concentration of products increases.
Hence, after three seconds, the rate would be lower, and the concentration of products would be higher.
https://brainly.com/question/23761331
Fusion reactions power the _____ in space. Humans currently use fusion in _____ , but researchers are seeking more applications.
Answer:
Sun and the stars, nothing humans don't use fusion at all
Explanation:
Nuclear fusion reactions power the sun in space. Humans currently use fusion in nuclear weapons by means of nuclear reactions, but researchers are seeking more applications.
What are nuclear reactions?There are two types of nuclear reactions which are nuclear fusion and nuclear fission .They involve the combination and disintegration of the element's nucleus respectively.
In nuclear fission, the nucleus of the atom is bombarded with electrons of low energy which splits the nucleus in to two parts .Large amount of energy is released in the process.It is used in nuclear power reactors as it produces large amount of energy.
In nuclear fusion,on the other hand, is a reaction which occurs when two or more atoms combine to form a heavy nucleus.Large amount of energy is released in the process which is greater than that of the energy which is released in nuclear fission process.
Learn more about nuclear reactions,here:
https://brainly.com/question/12649087
#SPJ7
I have a flask filled with water and on top a stopper .
I heat it over a flame .
after some time what will happen to the stopper
Answer:
A vacuum flask (also known as a Dewar flask, Dewar bottle or thermos) is an insulating storage vessel that greatly lengthens the time over which its contents remain hotter or cooler than the flask's surroundings. Invented by Sir James Dewar in 1892, the vacuum flask consists of two flasks, placed one within the other and joined at the neck. The gap between the two flasks is partially evacuated of air, creating a near-vacuum which significantly reduces heat transfer by conduction or convection.

The typical design of a Thermos brand vacuum flask, used for maintaining the temperature of fluids such as coffee.

Laboratory Dewar flask, Deutsches Museum, Munich

Diagram of a vacuum flask

A cryogenic storage dewar of liquid nitrogen, used to supply a cryogenic freezer
Vacuum flasks are used domestically, to keep beverages hot or cold for extended periods of time, and for many purposes in industry.
pls make me as brainliest
When 3.20 moles of magnesium is heated and placed in a container of nitrogen gas the two substances undergo a synthesis reaction. How many moles of nitrogen gas will react? 3 Mg (s) + 1 N2 (g) → 1 Mg3N2 (s)
Answer:
1.06 moles of nitrogen gas will react with 3.20 moles of magnesium in the container.
Explanation:
[tex]3 Mg (s) + 1 N_2 (g) \rightarrow 1 Mg_3N_2 (s)[/tex]
Moles of magnesium heated = 3.20 mol
According to reaction, 3 moles of magnesium reacts with 1 mole of nitrogen gas, then 3.20 moles of magnesium will react with:
[tex]=\frac{1}{3}\times 3.20 mol=1.07 \text{ mol of }N_2[/tex]
1.06 moles of nitrogen gas will react with 3.20 moles of magnesium in the container.
what element does HgNo
Answer:
Mercury is a chemical element with symbol Hg and atomic number 80. Classified as a transition metal, Mercury is a liquid at room temperature.
...
Explanation:
Answer:
Mercurous nitrate!
Juan Carlos placed 35 grams of ice into a dry, 200-gram container. The top
of the container was attached tightly. When the ice was completely melted, the
student measured the mass of the container with the liquid water. What should the
mass of the liquid water in the container be?
A. 35 grams
B. 165 grams
C. 200 grams
D. 235 grams
Mass of the liquid water in the container is 35 grams-
Mass doesn't depends upon the state of compounds.The mass of the liquid water in the container should be 35 grams.
Mass would not change during a change of state because the number of particles does not change during a state change. It does not matter if a substances freezes, boils, melts, sublimates.
So, the mass of liquid water in the container is the same as ice. Hence, the correct option is (A).
To know more about:-
brainly.com/question/11810264
Tides are the rise and fall of surface levels of Earth's ocean water caused by the gravitational effects of which two celestial objects?
A)stars and planets
B)comets and meteors
C)earthquakes and volcanoes
D)moon and sun
Answer:
D)Moon and sunExplanation:
Because the gravitational pull of the moon is weaker on the far side of the Earth, inertia wins, the ocean bulges out and high tide occurs.
hope it helps:)
Who has played Amoung us and a stranger got ur number or location on there?
Yep, it happened to me
which of the following does not contain a covalent bond ( please answer asap!! )
Answer:
Option 4
Explanation:
In a neutral solution, the concentration of H+ is
Group of answer choices
Answer:
equal to [OH-]
Hydrogen ion concentration is more conveniently expressed as pH, which is the logarithm of the reciprocal of the hydrogen ion concentration in gram moles per liter. Thus, in a neutral solution the hydrogen ion (H+) and the hydroxyl ion (OH−)
When patterns of stars appear to move across the sky, it provides evidence that ________.
A. Earth and stars move together
B. Earth rotates in space
C. patterns of stars can change
D. stars actually move
Answer:
Answered B
Explanation:
The earth moves which makes the stars and everything in space seem like its moving
Water flows more easily than syrup, which means water has
A. higher viscosity than syrup
B. lower viscosity than syrup
C. equal viscosity to syrup
Answer:
lower viscosity than syrup
Answer:
higher viscosity than syrup flows more easily than syrup.
Please give me Brainliest answer
A 125 ml sample of gas is at STP how many moles of gas are in the sample
Answer:
5.58*10⁻³ moles of gas are in the sample.
Explanation:
The STP conditions refer to the standard temperature and pressure. Pressure values at 1 atmosphere and temperature at 0 ° C are used and are reference values for gases. And in these conditions 1 mole of any gas occupies an approximate volume of 22.4 liters.
Being 1000 mL equivalent to 1 L, then 125 mL is equal to 0.125 L. Then you can apply the following rule of three: if by STP conditions 22.4 L are occupied by 1 mole, 0.125 L are occupied by how many moles?
[tex]amount of moles=\frac{0.125 L*1 mole}{22.4 L}[/tex]
aomunt of moles= 5.58*10⁻³ moles
5.58*10⁻³ moles of gas are in the sample.
Answer:
5.58×10⁻³ moles of gas
Explanation:
There is a rule that says, that 1 mol of any gas, at STP is contained at 22.4L of volume.
We can apply a conversion factor
0.125 L . 1 mol / 22.4 L = 5.58×10⁻³ moles
Notice we converted volume from mL to L
We can also aply the Ideal Gases Law.
At STP we have 1 atm of pressure and 273.15K of T°
We replace data: 0.125 L . 1 atm = n . 0.082 . 273.15K
(0.125 L . 1 atm) / (0.082 . 273.15 K) = n
n = 5.58×10⁻³ moles