Answer:
[tex]\boxed {\boxed {\sf 1.393 *10^{24} \ atoms \ B}}[/tex]
Explanation:
1. Convert Grams to Moles
Use the molar mass (found on the Periodic Table) to convert from grams to moles.
Boron (B): 10.81 g/molUse this value as a ratio.
[tex]\frac {10.81 \ g \ B }{1 \ mol \ B}[/tex]
Multiply by the given number of grams.
[tex]25.00 \ g \ B *\frac {10.81 \ g \ B }{1 \ mol \ B}[/tex]
Flip the ratio so the grams of boron cancel out.
[tex]25.00 \ g \ B *\frac {1 \ mol \ B }{10.81 \ g \ B}[/tex]
[tex]25.00 *\frac {1 \ mol \ B }{10.81 }[/tex]
[tex]\frac {25.00 \ mol \ B }{10.81 }=2.312673451 \ mol \ B[/tex]
2. Convert Moles to Atoms
We use Avogadro's Number, 6.02*10²³: the number of particles (atoms, molecules, etc.) in 1 mole of a substance. In this case, the particles are atoms of boron.
[tex]\frac {6.02*10^{23} \ atoms \ B} {1 \ mol \ B}[/tex]
Multiply by the number of moles we calculated.
[tex]2.312673451 \ mol \ B *\frac {6.02*10^{23} \ atoms \ B} {1 \ mol \ B}[/tex]
The moles of boron cancel.
[tex]2.312673451 *\frac {6.02*10^{23} \ atoms \ B} {1 }[/tex]
[tex]2.312673451 *6.02*10^{23} \ atoms \ B} =1.39269195*10^{24} \ atoms \ B[/tex]
The original value of grams has 4 significant figures, so our answer should have the same. For the number we calculated, that is the thousandth place.
[tex]1.392\underline69195*10^{24} \ atoms \ B[/tex]
The 6 tells us to round the 2 to a 3.
[tex]1.393 *10^{24} \ atoms \ B[/tex]
25.00 grams of boron is equal to 1.393*10²⁴ atoms.
What is PO3 compound name?
Answer:
PHOSPHITE ION is the correct answer.
Explanation:
Hope this helped Mark BRAINLIEST!!!
HELP !
The provided balanced equation applies to the reaction that takes place between lithium hydroxide and sulfuric acid. 2LiOH + H2SO4 -> Li2SO4 + 2H2O .
If the reaction begins with 26.7 grams of lithium hydroxide (LIOH) and 164.08 grams of suite acid (H2SO4.), how many grams of lithium sulfate (Li2SO4,) is produced? Assume 100% yield . Round your answer to the nearest tenth of a gram .
Answer:
60g or 61.28g
Explanation:
Trust me on this I had the same problem as you
What is the best common way to convert fossil fuels into energy?
a. oxidation
b. reaction
c. combustion
d. neutralization
Multiple Choice
1. Think About the definition of remote sensing. Which of the following could be considered sensors?
2. When satellite images are analyzed a unit called the pixel is a key to calculating what?
3. One Pixel represents.
a temperature
a wind speed of 10 kilometers per hour
a land area of 30 by 30 meters
various colors depending on their size
Answer:
Remote sensing is the process of detecting and monitoring the physical characteristics of an area by measuring its reflected and emitted radiation at a distance (typically from satellite or aircraft). ... Cameras on satellites can be used to make images of temperature changes in the oceans.
2.The answer is Land Area. If you know the distance and scale at which the image was captured, than one pixel of the image is equal to an X amount of area. The land area is represented as one pixel in an image called Resolution.
3.A pixel is the smallest picture element addressable on a picture, it is a specific location, and at that location associated with that location, is color, intensity
a.mph (miles per hour), mph. knots, knots. m/s (meters per second), m/s. ft/s (feet per second), ft/s. km/h (kilometers per hour), km/h ...
Explanation:
7 kph 4.35 mph
8 kph 4.97 mph
9 kph 5.59 mph
10 kph
The apparatus or tools that could be considered as sensors are telecopes, probes and landsat satellites.
What is remote sensing?Remote sensing can be defined as a process that is used for the acquisition of information about a phenomenon or physical object on a planet without coming in close contact with it, especially through the use of a telecope, probe or landsat satellite.
When satellite images are analyzed by astronomers or scientists, a unit called the pixel is a key to calculating land area. Also, one pixel is a unit that represents a land area of 30 by 30 meters.
Read more on telescope here: https://brainly.com/question/18300677
1. A 1500kg car is being lifted by a hydraulic jack attached to a flat plate. Underneath the plate is
a pipe with radius 24cm.
a) If there is no net force on the car, calculate the pressure in the pipe.
Answer:
the pressure in the pipe in the case when there is no net force on the car is 81,726 N/m^2
Explanation:
a. The computation of the pressure in the pipe in the case when there is no net force on the car is shown below
As we know that
Pressure = F ÷ area
Also
F = mg
Now
= (1500 × 9.8) ÷π (0.24)^2
= 81,726 N/m^2
Hence, the pressure in the pipe in the case when there is no net force on the car is 81,726 N/m^2
On a hot day, a student places a glass of cold lemonade on a table outdoors. After a few minutes, water droplets have formed on the outside of the glass.
Is energy absorbed or released by the cold lemonade? Explain your answer.
Compare average kinetic energy for the air molecules and lemonade molecules when the student first places the lemonade outdoors. Explain your answer.
Explain how and why the water droplets form on the outside of the glass.
Answer:
ye but sdfajkd tryng to play me
Explanation:
Answer:
Vapor is released out of the lemonade because when you place it in a hot it will increase.
Explanation:
What caused the formation of Mammoth Caves?
during what part of the day (night or day) can a solar be observed? explain your answer.
subject is science, please help me thx yal
What do you think
about the Civil Rights
Movement?
Why must an electron absorb a quantum of energy to move to a higher energy level?
Answer:
For an electron they start at the first level (n=1) In order to move up to the next level (n=2) the amount of quantom energy to move to this next level the energy must be perfect in order to move. If the quantom energy is to small the electron it doesn't try.
A geologist conducts an investigation to determine the absolute age of a fossil. She then
repeats the procedure three times. Which BEST explains why she repeated the procedure
several times?
•It helps her develop better procedures
•It improves the accuracy of the results.
•She wants all the results to be different.
•She has more than one hypothesis to prove.
Answer:
it improves the accuracy of the results
When the air near the surface is heated, it rises, taking heat with it. The type of energy transfer involved here is what?
Which change is an environmental effect of destroying wetlands?
loss of habitat
less flooding
smog
acid rain
Answer: Trust me 100% plz its loss of habitat wat they said
Explanation:
Help! I need help on how to do these problems.
Answer:
a. 3; b. 5; c. 10; d. 12
Explanation:
pH is defined as the negative log of the hydronium concentration:
pH = -log[H₃O⁺] (hydronium concentration)
For problems a. and b., HCl and HNO₃ are strong acids. This means that all of the HCl and HNO₃ would ionize, producing hydronium (H₃O⁺) and the conjugate bases Cl⁻ and NO₃⁻ respectively. Further, since all of the strong acid ionizes, 1 x 10⁻³ M H₃O⁺ would be produced for a., and 1.0 x 10⁻⁵ M H₃O⁺ for b. Plugging in your calculator -log[1 x 10⁻³] and -log[1.0 x 10⁻⁵] would equal 3 and 5, respectively.
For problems c. and d. we are given a strong base rather than acid. In this case, we can calculate the pOH:
pOH = -log[OH⁻] (hydroxide concentration)
Strong bases similarly ionize to completion, producing [OH⁻] in the process; 1 x 10⁻⁴ M OH⁻ will be produced for c., and 1.0 x 10⁻² M OH⁻ produced for d. Taking the negative log of the hydroxide concentrations would yield a pOH of 4 for c. and a pOH of 2 for d.
Finally, to find the pH of c. and d., we can take the pOH and subtract it from 14, giving us 10 for c. and 12 for d.
(Subtracting from 14 is assuming we are at 25°C; 14, the sum of pH and pOH, changes at different temperatures.)
Use the periodic table to select which type of bond is present and which of the listed properties is most likely for each substance.
A =
B =
Answer:
a= Covalent
b=low melting point
c= ionic
d=conduct electricity when dissolved
Explanation:
What type of plate boundary is
shown in the diagram below?
How many moles of copper would be needed to make one mole of cu2o?
Answer:
Explanation:
You can view more details on each measurement unit: molecular weight of Copper(I) Oxide or grams The molecular formula for Copper(I) Oxide is Cu2O. The SI base unit for amount of substance is the mole. 1 mole is equal to 1 moles Copper(I) Oxide, or 143.0914 grams.
What does an electromagnetic spectrum refer to?
O A. The energy of a photon emitted when an electron changes energy
levels
B. An angled piece of glass that splits up light into different
wavelengths
O C. A range of wavelengths of light that increases from one end to the
other
O D. The relationship between energy, wavelength, and frequency of
light
SUBMIS
Answer:
Explanation:
Option C is the correct answer
Among electromagnetic waves, UV rays are most dangerous because exposure to these radiation cause serious problems in living organism. Therefore, the correct option is option C.
What is electromagnetic wave?Electromagnetic wave is a wave which contain two component one is electric component and other is magnetic component. The electric and magnetic component are perpendicular to each other. There are so many wave that comes under electromagnetic wave like infrared wave , radio wave.
There is a relation between energy of wave. frequency of wave, and wavelength of wave
Mathematically,
E=hc/λ
where,
E = energy of electromagnetic wave
h is planks constant having value 6.67×10⁻³⁴js
c is speed of light that is 3×10⁸m/s
λ is the wavelength of electromagnetic wave
An electromagnetic spectrum refer to a range of wavelengths of light that increases from one end to the other.
Therefore, the correct option is option C.
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how many neurons are in phosphorous
Answer:
16 neutrons
hope this helped
Answer:
There are approximately 31 Neutrons in Phosphorous.
Explanation:
The atomic number for Phosphorous is 15
The element category for Phosphorous is non-metal
The number of Neutrons in Phosphorous are 31
Hope this helps! :)
Someone help please?- Ill give brainilist.
Answers:
1. Carbon is to organic as silicon is to inorganic
2. Sugar is to carbohydrate as oil is to lipid
Determine the mass in grams of 0.69 mol of gold (Au)
Answer:
We assume you are converting between moles Gold and gram. You can view more details on each measurement unit: molecular weight of Gold orgrams The molecular formula for Gold is Au. The SI base unit for amount of substance is the mole. 1 mole is equal to 1 moles Gold, or 196.96655grams.
Any corrections I need to make? Please help! And provide an actual answer please! Thank you!
Answer:
nah you good
Explanation:
it's perfect don't doubt yourself
Ben wants to test whether the material used to make a disposable cup affects the amount of thermal energy transferred to a person's hand. He investigates by carefully pouring the same volume of 90°C water into a foam cup and into a paper cup.
Which additional step in the investigation will help Ben determine which material reduces thermal energy (heat) transfer to the hand of a person holding the cup?
A.Stir the water in each cup for 10 minutes before measuring its temperature.
B.Measure the outside surface temperature of each cup after 10 minutes.
C.Vary the amount of water held by each cup before measuring its temperature.
Answer:
The answer would be B
Explanation:
C does not make sense and A will not affect anything
Measure the outside surface temperature of each cup after 10 minutes is the additional step in the investigation.
What is Temperature?This is defined as the degree of hotness or coldness of a substance and is measured in Celsius or Kelvin.
Determining which material reduces thermal energy will involve measuring the outside surface temperature of each cup after 10 minutes for the difference.
Read more about Temperature here https://brainly.com/question/24325419
What is the pH at the equivalence point in the titration of 10.0 mL of 0.39 M HZ with 0.200 M NaOH? Ka = 2.4 × 10−6 for HZ.
Answer:
pH = 9.37
Explanation:
The reaction of HZ with NaOH occurs as follows:
HZ + NaOH → H₂O + Na⁺ + Z⁻
When the reaction is in the equivalence point, the moles added of HZ = Moles of NaOH.
At equivalence point, you will have in solution just NaZ that is in equilibrium with water as follows:
Z⁻(aq) + H₂O(l) ⇄ OH⁻(aq) + HZ(aq)
Where K of equilibrium is Kw / Ka = 1x10⁻¹⁴ / 2.4x10⁻⁶ = 4.17x10⁻⁹
And K is defined as:
K = 4.17x10⁻⁹ = [OH⁻] [HZ] / [Z⁻]
To solve this question we must find [Z⁻] and as [OH⁻] and [HZ] comes from the same equilibrium, both are equal and we can find [OH⁻] in order to solve pH:
Moles NaOH added = Moles HZ:
0.010L * (0.39mol / L) = 3.9x10⁻³ moles HZ = Moles NaOH added
The volume of 0.200M NaOH must be:
3.9x10⁻³ moles * (1L / 0.200moles) = 0.0195L.
The moles of HZ = Moles Z⁻ after the reaction and the volume is 0.010L + 0.0195L = 0.0295L. Thus, [Z⁻] is:
[Z⁻] = 3.9x10⁻³ moles / 0.0295L
[Z⁻] = 0.132M
Replacing in K expression:
4.17x10⁻⁹ = [OH⁻] [HZ] / [Z⁻]
4.17x10⁻⁹ = [X] [X] / [0.132]
5.51x10⁻¹⁰ = X²
X = 2.35x10⁻⁵M = [OH⁻]
As pOH = -log [OH⁻]
pOH = 4.63
And pH is
pH = 14 -pOH
pH = 9.37Write out and BALANCE the following equation: Solid Scandium metal
reacts with water to produce Scandium(III) oxide and hydrogen gas.
15 point
what is the enthalpy of the overall chemical reaction ch4(g)+4cl2(g)- ccl4(g)+4hcl(g)?
1. -205.7kj
2. -113.4kj
3. -14.3kj
4. 78.0kj
Answer:
-205.7kj
Explanation:
Now adding reaction 2 and twice of reaction 3 and reverse of reaction 1, we get the enthalpy of the reaction.
The expression for enthalpy for the following reaction will be,
where,
n = number of moles
Now put all the given values in the above expression, we get:
Therefore, the enthalpy of the following reaction is, -205.7kj
Help me please!
What is the solubility of KNO3 in 100g of water at 60°C?
A.
28 grams/100g of H2O
B.
45 grams/100g of H2O
C.
108 grams/100g of H2O
D.
38 grams/100g of H2O
Answer:
C. 108 grams/100g of H2ORequired number is the vertical coordinate of the intersection point of a line at 60°C with the graph of the KNO₃.
This sea grass has had the sun shining on it for most of the day. What can the sea grass do because it is in sunlight? What does this mean for the number of energy storage molecules in the sea grass?
The sea grass can
Answer:
I don't really get your question but I think my answer relates to your question :)
Explanation:
Due to the high availability of sunlight, sea grass can get the sufficient light energy to carry photosynthesis and storage of energy.
What is photosynthesis ?Photosynthesis is a biochemical process by which green plants synthesis energy and in the leaves by the aid of light energy. Here, the light energy is converted to chemical energy.
Plants need sunlight for the light reaction of photosynthesis. In the absence of sunlight, they cant synthesis energy and the chlorophyll does not get active. They will grow towards sunlight.
The sea grass are getting sufficient light energy for the synthesis of energy. The energy storage molecules ie. ATP in sea grass will be synthesized in higher rate with the presence of sun shining.
Find more on photosynthesis:
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S8 + 12 O2 —> 8 SO3 what volume of oxygen would be required to completely react with 45.7g of S8
Answer:
47.9L of oxygen would be required
Explanation:
Assuming oxygen gas is at STP
Based on the reaction:
S₈ + 12 O₂ → 8SO₃
1 mole of S₈ (Molar mass: 256.52g/mol) reacts with 12 moles of oxygen.
To solve this question we must find the moles of S₈ added. With the reaction we can find the moles of O₂ and using PV = nRT we can find the volume of oxygen required:
Moles S₈:
45.7g * (1mol / 256.52g) = 0.178 moles S₈
Moles O₂:
0.178 moles S₈ * (12 moles O₂ / 1mol S₈) = 2.138 moles O₂
Volume O₂:
PV = nRT
V = nRT / P
Where V is volume
n are moles = 2.138 moles
R is gas constant 0.082atmL/molK
T is absolute temperature = 273.15K at sTP
P is pressure = 1 atm at STP
V = 2.138mol*0.082atmL/molK*273.15K / 1atm
V = 47.9L of oxygen would be required
Answer:
180.2 L
Explanation:
Please help, I'm so confused!!!!
Answer:
[tex]\boxed {\boxed {\sf N_2}}[/tex]
Explanation:
Let's examine this reaction, especially the coefficients.
[tex]N_2+3H_2 \rightarrow 2NH_3[/tex]
First of all, remember that reactants are used to make the product. They are found on the left of the arrow usually. Therefore, N₂ and H₂ are the reactants, while NH₃ is the product. We can automatically eliminate NH₃ from our answer choices, because it is simply not a reactant.
Next, look at the coefficients.
N₂ has no coefficient, so a 1 is implied. H₂ has a coefficient of 3.Therefore, for the reaction to work, there must be 1 mole of N₂ and 3 moles of H₂.
We have 3.2 moles of N₂ and 5.4 moles of H₂.
Divide each amount given by the required amount for completion.
3.2 mol N₂/ 1 mol N₂= 3.2 times 5.4 mol H₂/ 3 mol H₂=1.8 timesTherefore, there is enough nitrogen to complete the reaction 3.2 times, but only enough hydrogen for 1.8 times. If everything is completely reacted, we will run out of hydrogen and have excess nitrogen.