Answer:
There are 10.0 moles of beryllium oxide in a 250 grams sample of the compound.
Explanation:
We can calculate the number of moles (η) of BeO as follows:
[tex] \eta = \frac{m}{M} [/tex]
Where:
m: is the mass = 250 g
M: is the molar mass = 25.0116 g/mol
Hence, the number of moles is:
[tex] \eta = \frac{250 g}{25.0116 g/mol} = 10.0 moles [/tex]
Therefore, there are 10.0 moles of beryllium oxide in a 250 grams sample of the compound.
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Explain how it's possible that warm temperatures can cause more snow to happen.
Determine if the bond between atoms in each example below is nonpolar covalent, polar covalent, or ionic a. H-H b. P-Cl c. F-F d. Na-Br e. N-F f. Mg-O g. C-H h. H-Cl
Answer:
a nonpolar covalent
b polar
c nonpolar
d ionic
e. polar
f. ionic
g polar
h polar
Explanation:
A) Calculate the vapor pressure of a 7% by mass benzaoic acid in ethanol solution at 30°C. The vapor pressure of pure ethanol at this temperature is 13.40 kPa. ( assume a 100 g of solution)
B) Calculate the boiling point of the solution above
Answer:
the answer is C
Explanation:
Liquid hexane will react with gaseous oxygen to produce gaseous carbon dioxide and gaseous water . Suppose 17.2 g of hexane is mixed with 19. g of oxygen. Calculate the maximum mass of carbon dioxide that could be produced by the chemical reaction. Be sure your answer has the correct number of significant digits.
Answer:
16.5g of CO₂ could be produced
Explanation:
The combustion of hexane occurs as follows:
C₆H₁₄(l) + 19/2O₂ → 6CO₂ + 7H₂O
Where 1 mole of hexane reacts with 19/2 moles of O₂.
To solve this question we need to find the moles of each reactant in order to find limiting reactant. The moles of the limiting reactant will determine the moles of CO₂ produced:
Moles C₆H₁₄ -Molar mass: 86.18g/mol-:
17.2g hexane * (1mol / 86.18g) = 0.200 moles hexane
Moles O₂ -Molar mass: 32g/mol-:
19g O₂ * (1mol / 32g) = 0.594 moles oxygen.
For a complete reaction of 0.594 moles of oxygen are required:
0.594 moles O₂ * (1mol C₆H₁₄ / 19/2 moles O₂) = 0.0625 moles C₆H₁₄.
As there are 0.200 moles of hexane, hexane is the excess reactant and oxygen the limiting reactant.
The moles of CO₂ produced assuming a yield of 100% -All moles of oxygen react producing carbon dioxide.:
0.594 moles O₂ * (6mol CO₂ / 19/2 moles O₂) = 0.375 moles of CO₂ could be produced. The mass is:
0.375 moles of CO₂ * (44.01g / mol) =
16.5g of CO₂ could be producedPut these elements in order of decreasing electronegativity, with the highest electronegative element as number 1.
a. tin (Sn, Group 14, Period 5)
b. rubidium (Rb, Group 1, Period 5)
c. bromine (Br, Group 17, Period 4)
d. lithium (Li, Group 1, Period 2)
e. cadmium (Cd, Group 12, Period 5)
Answer:the answer is a c and e
Explanation:
An allergy medicine is usually stored in a cabinet at room termperature where its molecules move around each other. By
mistake, an intern transferred energy into the medicine. After one hour, the intern found the medicine and noticed that it
was a liquid. How were the molecules moving when the intern found the medicine? Explain why the molecules were
moving this way after the intern transferred energy ito the medicine.
Answer:
hello, can you pleas egive me the answer? i have the same exact question. thank you!
Explanation:
write the chemical equation of the reaction with a change in colour
Answer:
(i) Change in colour (ii) Change in temperature (iii) Formation of precipitate
Explanation:
(i) Change in colour: Reaction between lead nitrate solution and potassium iodide solution. Pb(NO3)2(aq)+2KI → PbI2(s)+2KNO3(aq) In this reaction, colour changes from colourless to yellow. (ii)Change in temperature: Action of dilute sulphuric acid on zinc. Zn(s) + H2SO4(aq) → ZnSO4(aq) + H2 In this reaction, heat is evolved (iii) Formation of precipitate: Action of barium chloride on sodium sulphate. BaCl2(aq) +Na2SO4(aq) → BaSO4(s) +2NaCl(aq) BaSO4(s)
Sodium metal reacts with chlorine gas to produce crystals of sodium
chloride. Show phases in your equation.
Answer:
Na(s) + Cl(g) = NaCl(s)
Explanation:
s means solid
g means gas
Metals are solid at room temperature.
Crystals are solids
Help pls! I need help im just writing to use the character limit!
Answer:
se que la imaje es un poco confusa con la materia pero
desiaria ayudarte pero CREO que con mi TÉCNICA es la A
How many moles of hydrogen sulfide are contained in a 77.7-8 sample of this gas?
Select one:
o
a. 0.44mol
O b.4.56mol
O c. 38.5mol
O d. 111.8mol
e. 2.28mol
Answer:
its either C or D my guess is C though because 35.0g of hyddrogen is =1.03 mol
Explanation:
how much energy must be released by 50.0 g of steam to decrease its temperature from 125.0 degrees Celsius to 100.0 degrees Celsius ?
Answer:
5250 Joules
Explanation:
Mass = 50g
Initial Temperature = 125.0 degrees Celsius
Final Temperature = 100 degrees Celsius
Temperature change = Final - Initial = 100 - 125 = -25
Heat = ?
These quantities are related by the equation;
H = mCΔT
where c = specific hear capacity = 4.2 J/g°C
H = 50 * 4.2 * (-25)
H = -5250 J (The negative sign is because heat is being released)
Explain three types eye protection and their appropriate uses
Answer:
safety glasses, safety goggles, face shield, they protect your eyes from harmful liquids, bright lights
How are scientists trying to use a plant catalyst to create solar fuels? Someone please answer?
Answer:
plants can be used as fuel because plants can be burned so they compose the plants to make a liquid
Which of the following is true?
A)If we know that a reaction is an elementary reaction, then we know its rate law.
B)The rate-determining step of a reaction is the rate of the fastest elementary step of its mechanism.
C)Since intermediate compounds can be formed, the chemical equations for the elementary reactions in a multistep mechanism do not always have to add to give the chemical equation of the overall process.
D)In a reaction mechanism, an intermediate is identical to an activated complex.
E)all of these statements are true.
Answer:
If we know that a reaction is an elementary reaction, then we know its rate law.
Explanation:
An elementary reaction is a reaction that takes place in one reactive encounter. This means that the two species interact in a single step to give the products.
If two reactants interact in a single step to yield the products then we can easily deduce the rate law from the reaction equation.
For instance, For the reaction;
2A + B → C
The rate law is
rate = k[A]²[B].
If the reaction is an elementary reaction and the equation of the reaction is balanced, then we can deduce the rate law from the balanced reaction equation.
Define atmosphere and list any three ways in which
the atmosphere is useful for the survival of living
things.
Answer:
Explanation:
Atmosphere - the envolpoe of gasses sourounding the earth or another planet or the air in any particular place. The atmosphere protects us from the suns harmful rays, carrys cloud full of water so it can rain all over the world, and have oxygen, which is nessecary for survival to all living things.
A relationship in which one variable increases as the other variable decreases is an inverse relationship.
CA. True
B. False
Answer:
TRUE
Explanation:
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help me plss it’s kinda easy but i’m not sure
Answer:
Sexual Reproduction
Explanation:
In Asexual Reproduction offsprings are know as ramets and many ramets are known as clowns. So, when two parents are involved genetic variations occur in offspring. Pollen possess male gamete (antherozoid/sperm) and ovule possess egg.
A part
which one is the correct ans.
Answer:
Aluminium Sulphate
Explanation:
Aluminium sulphate is the most widely used aluminium coagulant. It is soluble in water and used as a coagulating agent in purification of drinking water and in waste water treatment plants.
Answer:
where are you from .. ...
According to the combined gas law, pressure is inversely proportional to volume and directly proportional to temperature, and volume is directly proportional to temperature.
True
B. False
Save & Cont
Which statement best explains how the solution should be made?
A) Add 1.5 mL of 0.50 M H2SO4 to 10.5 mL of water to get 12 mL of 4 M H2SO4.
B) Add 1.5 mL of 4.00 M H2SO4 to 10.5 mL of water to get 12 mL of 0.50 M H2SO4.
C) Add 1.5 mL of 4.00 M H2SO4 to 12 mL of water to get 0.50 M H2SO4.
Answer:
B
Explanation:
Correct on Edge
The pressure 15.0 m under water is 248 kPa.
What is this pressure in torr
Answer:
1860 torr
Explanation:
In order to convert from kPa to torr, we are going to use the following conversion factor:
1 kPa = 7.5 torrNow we multiply 248 kPa with this factor so that the kPa units cancel each other and only the torr units remain:
248 kPa * [tex]\frac{7.5torr}{1kPa}[/tex] = 1860 torrThis means that the answer is 1860 torr.
Connor turns on a hair dryer to style his hair in the morning. Which choice identifies all of the energy transformations in the system?
electrical -- heat sound, and motion
electrical -- sound and motion
heat-electrical and sound
heat and sound -motion
Answer:
It is electrical → heat, sound, and motion
because a hair dryer makes heat to dry your hair and sound is the blowing and motion is how it goes
Explanation:
Answer:
A
Explanation:
electrical -- heat sound, and motion
Aside from invasives like the crown-of-thorns starfish, what other factor is killing the Great Barrier Reef?
O increased temperatures
O overactive algae
O reactive forms of oxygen
O coral bleaching
Answer:
increased temperatures
Explanation:
The temperatures are increasing in the ocean because of ocean warming, by climate change. The heat in the ocean stresses healthy corals, which drains them of their vibrant colors, known as bleaching.
How many grams of sodium (Na) are in 6.2 mol of Na?
mass = mol no. x molar mass
= 6.2 x 23
= 142.6 g
Ve. In what layer do weather balloons fly?
Earth layers
Answer:
stratosphere
Explanation:
what are three limitations of current cloaking technology.
Get this correct I'll give you 40 points.
Explanation:
1.undetectable to electromagnetic waves
2.hiding an object from an illumination containing diffre t wave lengths become difficult as the object sizes grow.
3. reduce the scattering by two orders.
Electromagnetic waves are unable to detect it. With increasing item sizes, it becomes more challenging to conceal an object from an illumination with various wave lengths. two orders down on the scattering.
What is current cloaking technology?
Current clocking technology is defined as a hypothetical or made-up stealth technology that makes things like people or spaceships completely or partially invisible to certain electromagnetic (EM) spectrum wavelengths. In a specific frequency band, this gadget renders an object "invisible" to electromagnetic radiation. Obviously, cloaks that operate in the visible spectrum have the most fascinating potential uses.
These metamaterials, according to the researchers, can shield a medium-sized antenna from radio waves over a wide range of bandwidths, resulting in clearer communications. However, as visible light wavelengths are far shorter than radio waves, it is practically difficult to conceal huge things from them, such as the human body. The issue with present designs is that they can only handle a certain amount of bandwidth. Even this "perfect" 3D cloak that was previously exhibited could only conceal items from microwaves.
Thus, electromagnetic waves are unable to detect it. With increasing item sizes, it becomes more challenging to conceal an object from an illumination with various wave lengths. two orders down on the scattering.
To learn more about current cloaking technology, refer to the link below:
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15POINTS!!! And brainliest
Answer: a. 3.36 L
b. 33.2 g
Explanation:
According to avogadro's law, 1 mole of every substance occupies 22.4 L at STP and contains avogadro's number [tex]6.023\times 10^{23}[/tex] of particles.
Standard condition of temperature (STP) is 273 K and atmospheric pressure is 1 atm respectively.
To calculate the number of moles, we use the equation:
[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex]
[tex]\text{Number of moles of} Fe_2O_3=\frac{16.0g}{159.69g/mol}=0.1mole[/tex]
[tex]3O_2(g)+4Fe(s)\rightarrow 2Fe_2O_3(s)[/tex]
a. 2 moles of [tex]Fe_2O_3[/tex] are produced by = [tex]3\times 22.4L=67.2L[/tex] of [tex]O_2[/tex]
Thus 0.1 moles of [tex]Fe_2O_3[tex] are produced by =[tex]\frac{67.2}{2}\times 0.1=3.36L[/tex] of [tex]O_2[/tex]
b. [tex]3\times 22.4L=67.2L[/tex] of [tex]O_2[/tex] react with = [tex]4\times 55.8=223.2g[/tex] of iron
Thus 10.0 L of [tex]O_2[/tex] react with = [tex]\frac{223.2}{67.2}\times 10=33.2g[/tex] of iron
The spot on the fault where the pressure first releases is called the
Answer:
This movement releases energy and generates seismic waves that can be recorded by specialized instruments used by scientists. The point on a fault at which the first movement or break occurs during an earthquake is called the earthquake's hypocenter
Explanation:
A balloon of hydrogen is subjected to vacuum. The initial pressure and volume of hydrogen is 0.95 atm and 0.55 L. Calculate the final pressure if the final volume is 1.22 L?
Answer:
0.43 atm
Explanation:
From the question given above, the following data were obtained:
Initial pressure (P₁) = 0.95 atm
Initial volume (V₁) = 0.55 L
Final volume (V₂) = 1.22 L
Final pressure (P₂) =?
The final pressure of the gas can be obtained by using the Boyle's law equation as follow:
P₁V₁ = P₂V₂
0.95 × 0.55 = P₂ × 1.22
0.5225 = P₂ × 1.22
Divide both side by 1.22
P₂ = 0.5225 / 1.22
P₂ = 0.43 atm
Therefore, the final pressure of the gas is 0.43 atm
The final pressure of the gas is 0.43 atm.
What is pressure?Pressure is the process of force exerted perpendicular to any surface.
Given, the Initial pressure (P₁) is 0.95 atm
The initial volume (V₁) is 0.55 L
The final volume (V₂) is 1.22 L
To find the final pressure (P₂)
By the Boyle's Law
[tex]\rm P_1V_2= P_2V_2[/tex]
[tex]\rm 0.95\times 0.55 = P_2\times1.22\\\\0.5225 = P_2 \times 1.22\\\\Divided\;both \;side\;by\;1.22\\\\P_2=\dfrac{0.5225}{1.22} = 0.43 atm.[/tex]
Thus, the final pressure of the gas is 0.43 atm.
Learn more about pressure, here:
https://brainly.com/question/356585