Answer:
3.7 x 10²¹ O₂ molecules
Explanation:
2KClO₃ => 2KCl + 3O₂
given 0.500g KClO₃ => 0.500g/122.55g/mol = 0.0041 mole KClO₃
0.0041 mole KClO₃ => 3/2(0.0041) mole O₂ = 0.0061 mole O₂
0.0061 mole O₂ = 0.0061 mole O₂ x 6.02 x 10²³ molecules O₂/mole O₂
= 3.7 x 10²¹ molecules O₂
Calculate the moles of argon gas at STP in 33 L. Round answer to 2 significant figures.
Answer:
1.5 mol
Explanation:
Step 1: Given data
Volume of argon gas: 33 LStandard temperature: 273.15 KStandard pressure: 1 atmStep 2: Calculate the moles corresponding to 33 L of argon at standard temperature and pressure (STP)
At STP, 1 mole of argon gas occupies 22.4 L.
33 L × 1 mol/22.4 L = 1.5 mol
Using the rules that we developed in this chapter (ARIO), we might have expected these two compounds to have the same pKa. Nevertheless, they are different. Salicylic acid is apparently more acidic than its constitutional isomer. Can you offer an explanation for this observation
Answer:
The correct answer is
- after deprotonation carboxylic acid stabilizes by binding -OH group with hydrogen bonding in salicylic acid and while it's not possible with its constitutional isomer (para-hydroxy benzoic acid).
The more electronegative atoms are replaced by the H atom of the carboxylic group and form more stabilize carboxylic acid which not takes place in para-hydroxy benzoic acid.
What is the entropy of this collection of training examples with respect to the positive class B. What are the information gains of A1 and A2 relative to the training dataset For A3, which is a continuous attribute, compute the information gain for every possible split. C. What is the best split (among A1,A2, and A3) according to the information gain
The data set is missing in the question. The data set is given in the attachment.
Solution :
a). In the table, there are four positive examples and give number of negative examples.
Therefore,
[tex]$P(+) = \frac{4}{9}$[/tex] and
[tex]$P(-) = \frac{5}{9}$[/tex]
The entropy of the training examples is given by :
[tex]$ -\frac{4}{9}\log_2\left(\frac{4}{9}\right)-\frac{5}{9}\log_2\left(\frac{5}{9}\right)$[/tex]
= 0.9911
b). For the attribute all the associating increments and the probability are :
[tex]$a_1$[/tex] + -
T 3 1
F 1 4
Th entropy for [tex]$a_1$[/tex] is given by :
[tex]$\frac{4}{9}[ -\frac{3}{4}\log\left(\frac{3}{4}\right)-\frac{1}{4}\log\left(\frac{1}{4}\right)]+\frac{5}{9}[ -\frac{1}{5}\log\left(\frac{1}{5}\right)-\frac{4}{5}\log\left(\frac{4}{5}\right)]$[/tex]
= 0.7616
Therefore, the information gain for [tex]$a_1$[/tex] is
0.9911 - 0.7616 = 0.2294
Similarly for the attribute [tex]$a_2$[/tex] the associating counts and the probabilities are :
[tex]$a_2$[/tex] + -
T 2 3
F 2 2
Th entropy for [tex]$a_2$[/tex] is given by :
[tex]$\frac{5}{9}[ -\frac{2}{5}\log\left(\frac{2}{5}\right)-\frac{3}{5}\log\left(\frac{3}{5}\right)]+\frac{4}{9}[ -\frac{2}{4}\log\left(\frac{2}{4}\right)-\frac{2}{4}\log\left(\frac{2}{4}\right)]$[/tex]
= 0.9839
Therefore, the information gain for [tex]$a_2$[/tex] is
0.9911 - 0.9839 = 0.0072
[tex]$a_3$[/tex] Class label split point entropy Info gain
1.0 + 2.0 0.8484 0.1427
3.0 - 3.5 0.9885 0.0026
4.0 + 4.5 0.9183 0.0728
5.0 -
5.0 - 5.5 0.9839 0.0072
6.0 + 6.5 0.9728 0.0183
7.0 +
7.0 - 7.5 0.8889 0.1022
The best split for [tex]$a_3$[/tex] observed at split point which is equal to 2.
c). From the table mention in part (b) of the information gain, we can say that [tex]$a_1$[/tex] produces the best split.
Why do you think there are different stars in each nighttime section of the artifact?
Answer:
The sky looks different in each nighttime section of the artifact because the artifact sections represent different seasons. ... Different constellations are visible on different nights throughout the year because of the earth's orbit. The Earth orbits around the sun. A full orbit is 365 days or one year.
Explanation:
What products will form when bromine is added to gallium chloride?*
A.)no reaction will occur
B.)gallium bromide and chlorine
C.)gallium bromine and chloride
D.)bromine chloride and gallium
Would a salt-cured egg be a physical or chemical change?
For a science experiment, I placed an egg in water that had three tablespoons of salt for one week. After 4 days, the egg cracked. At the end of the week, I took it out and cracked the egg. The egg yolk was now solid. This is also called salt-cured eggs. However, I'm not sure whether this is a physical or chemical change.
Answer:
I believe it is a physical change
Explanation:
The telltale sign of a chemical change is the formation of a new substance. They also usually involve the production of energy (heat, light, sound etc.)
Element R has three isotopes. The isotopes are present in 0.0825, 0.2671, and 0.6504 relative
abundance. If their masses are 81, 115, and 139 respectively, calculate the atomic mass of element
R. (No decimals).
The average atomic mass of the element R that has three isotopes is 127.805.
How to calculate average atomic mass?Average atomic mass is the weighted average of the atomic masses of the naturally occurring isotopes of an element.
The average atomic mass of an element can be calculated by summing up the product of the percent abundance and masses of each isotope as follows;
Average atomic mass of R = (0.0825 × 81) + (0.2671 × 115) + (0.6504 × 139)
Average atomic mass = 6.6825 + 30.7165 + 90.4056 = 127.805
Learn more about average atomic mass at: https://brainly.com/question/13753702
#SPJ1
Element R has three isotopes. The isotopes are present in 0.0398, 0.1614, and 0.7988 relative
abundance. If their masses are 191, 180, and 143 respectively, calculate the atomic mass of element
R. (No decimals)
The atomic mass of element R is 151 (no decimals).
To calculate the atomic mass of element R, we need to consider the relative abundance of each isotope and its corresponding mass. The atomic mass is the weighted average of the masses of all the isotopes, taking into account their relative abundance.
Given:
Isotope 1: Relative abundance = 0.0398, Mass = 191
Isotope 2: Relative abundance = 0.1614, Mass = 180
Isotope 3: Relative abundance = 0.7988, Mass = 143
To calculate the atomic mass, we multiply the relative abundance of each isotope by its mass, and then sum up the results.
Atomic mass = (Relative abundance of Isotope 1 * Mass of Isotope 1) + (Relative abundance of Isotope 2 * Mass of Isotope 2) + (Relative abundance of Isotope 3 * Mass of Isotope 3)
Atomic mass = (0.0398 * 191) + (0.1614 * 180) + (0.7988 * 143)
Calculating the values:
Atomic mass = 7.6098 + 29.0256 + 114.6872
Atomic mass = 151.3226
Rounding to the nearest whole number, the atomic mass of element R is 151.
For more such question on mass. visit :
https://brainly.com/question/24191825
#SPJ8
How many protons are in nitrogen
Answer:
Explanation:
There are 7 protons in nitrogen
7 TYPE OF NITRONGEN
. . .
If the solubility of salicylic acid is 77.8 g/L of water at 100oC and 1.4 g/L of water at 10oC, a) calculate the minimum amount (in mL) of boiling water necessary to dissolve 2.0 g of impure salicylic acid for recrystallization. b) If the solution is cooled to room temperature and then to 10oC with an ice/water bath, what is the maximum amount of solid salicylic acid isolated after vacuum filtration
Answer:
a. 25.7mL are necessaries.
b. 1.964g of salicylic acid can be isolated.
Explanation:
a. As the solubility of salicylicic acid in boiling water is 77.8g/L, to dissolve 2.0g of salicylic acid are necessaries:
2.0g * (1L / 77.8g) = 0.0257L =
25.7mL are necessariesb. Then, at 10°C the solution just can dissolve 1.4g/L, that is:
0.0257L * (1.4g/L) = 0.036g of salicylic acid are dissolved.
And will precipitate:
2.0g - 0.036g =
1.964g of salicylic acid can be isolatedwhy are electrical wires covered with plastic coating
Answer:
For safety.
Explanation:
Because uncovered wires are conductors, an electric current could damage someone if touched. Plastic and rubber are insulators, meaning that current cannot pass through them.
The Earth's asthenosphere is a structural layer
A.
that is made of the crust and the uppermost part of the mantle.
B.
that is contained completely within the crust.
C.
that is contained completely within the upper mantle.
D.
that is made of the mantle and the uppermost part of the crust.
Answer:
Dont completly trust me here but i think its a but id try and wait for someone else just be careful
Explanation:
Identify the substance that has formula mass of 133.5amu.
(a) MgCI
b)SCI
c)BCI
D) AICI
The calculated formula masses to 133.5 amu, we find that the substance with a formula mass closest to 133.5 amu is (d) AlCl3. Therefore, the answer is option D.
To identify the substance with a formula mass of 133.5 amu, we need to calculate the formula mass of each given substance and compare it to 133.5 amu.
(a) MgCl2:
The formula mass of MgCl2 can be calculated by adding the atomic masses of magnesium (Mg) and chlorine (Cl).
Mg: atomic mass = 24.31 amu
Cl: atomic mass = 35.45 amu
Formula mass of MgCl2 = (24.31 amu) + 2(35.45 amu) = 95.21 amu
(b) SCl:
The formula mass of SCl can be calculated by adding the atomic masses of sulfur (S) and chlorine (Cl).
S: atomic mass = 32.07 amu
Cl: atomic mass = 35.45 amu
Formula mass of SCl = 32.07 amu + 35.45 amu = 67.52 amu
(c) BCl:
The formula mass of BCl can be calculated by adding the atomic mass of boron (B) and chlorine (Cl).
B: atomic mass = 10.81 amu
Cl: atomic mass = 35.45 amu
Formula mass of BCl = 10.81 amu + 35.45 amu = 46.26 amu
(d) AlCl3:
The formula mass of AlCl3 can be calculated by adding the atomic mass of aluminum (Al) and 3 times the atomic mass of chlorine (Cl).
Al: atomic mass = 26.98 amu
Cl: atomic mass = 35.45 amu
Formula mass of AlCl3 = 26.98 amu + 3(35.45 amu) = 133.78 amu. Option D
For more such questions on masses visit:
https://brainly.com/question/24191825
#SPJ8
Aqueous solutions containing approximately 3 percent(w/w) H2O2 are sold in drug stores as a disinfectant. Determination of the actual concentration of H2O2 in a bottle of peroxide solution was done by diluting 1.50 mL to 100 mL with water, acidifying with dilute H2SO4 and titrating with a 0.01411 M KMnO4 solution. 32.17 mL of the permangate solution was needed to reach the end point of the titration. What is the actual molar concentration of the H2O2 solution]
Answer:
0.01804 M KMnO4 Solution.
Explanation:
3 Percent(w/w) H2O2 Are Sold In Drug Stores As A Disinfectant. ... H2O2 In A Bottle Of Peroxide Solution Was Done By Diluting 1.50 ML To 100 ML With Water, Acidifying With Dilute H2SO4 And Titrating With A 0.01804 M KMnO4 Solution.
Wich stament describes to organ systems working together to get rid of waste played by cells
Answer:
C. Kidneys filter wastes from the bloodstream and produce urine
Explanation:
Why do scientists think that liquid water might have once existed on Mars?
Answer: The discovery of three buried lakes. Scientists think that a long time ago there were lakes and rivers, etc on Mars. Now of course, you can't see any visible water sources on the surface.
Answer:
Almost all water on Mars today exists as ice, though it also exists in small quantities as vapor in the atmosphere.[5] What was thought to be low-volume liquid brines in shallow Martian soil, also called recurrent slope lineae may be grains of flowing sand and dust slipping downhill to make dark streaks.The only place where water ice is visible at the surface is at the north polar ice cap. Abundant water ice is also present beneath the permanent carbon dioxide ice cap at the Martian south pole and in the shallow subsurface at more temperate conditions. More than 5 million km3 of ice have been detected at or near the surface of Mars, enough to cover the whole planet to a depth of 35 meters. Even more ice is likely to be locked away in the deep subsurface.
Some liquid water may occur transiently on the Martian surface today, but limited to traces of dissolved moisture from the atmosphere and thin films, which are challenging environments for known life. No large standing bodies of liquid water exist on the planet's surface, because the atmospheric pressure there averages just 600 pascals , a figure slightly below the vapor pressure of water at its melting point; under average Martian conditions, pure water on the Martian surface would freeze or, if heated to above the melting point, would sublime to vapor. Before about 3.8 billion years ago, Mars may have had a denser atmosphere and higher surface temperatures, allowing vast amounts of liquid water on the surface, possibly including a large ocean that may have covered one-third of the planet.Water has also apparently flowed across the surface for short periods at various intervals more recently in Mars' history. Aeolis Palus in Gale Crater, explored by the Curiosity rover, is the geological remains of an ancient freshwater lake that could have been a hospitable environment for microbial life.Many lines of evidence indicate that water ice is abundant on Mars and it has played a significant role in the planet's geologic history.The present-day inventory of water on Mars can be estimated from spacecraft images, remote sensing techniques (spectroscopic measurements, radar, etc.), and surface investigations from landers and rovers.Geologic evidence of past water includes enormous outflow channels carved by floods, ancient river valley networks, deltas and lakebeds,and the detection of rocks and minerals on the surface that could only have formed in liquid water. Numerous geomorphic features suggest the presence of ground ice (permafrost)and the movement of ice in glaciers, both in the recent past and present. Gullies and slope lineae along cliffs and crater walls suggest that flowing water continues to shape the surface of Mars, although to a far lesser degree than in the ancient past.Although the surface of Mars was periodically wet and could have been hospitable to microbial life billions of years ago, the current environment at the surface is dry and subfreezing, probably presenting an insurmountable obstacle for living organisms. In addition, Mars lacks a thick atmosphere, ozone layer, and magnetic field, allowing solar and cosmic radiation to strike the surface unimpeded. The damaging effects of ionizing radiation on cellular structure is another one of the prime limiting factors on the survival of life on the surface. Therefore, the best potential locations for discovering life on Mars may be in subsurface environments. Large amounts of underground ice have been found on Mars; the volume of water detected is equivalent to the volume of water in Lake Superior. In 2018, scientists reported the discovery of a subglacial lake on Mars, 1.5 km (0.93 mi) below the southern polar ice cap, with a horizontal extent of about 20 km (12 mi), the first known stable body of liquid water on the planet.Understanding the extent and situation of water on Mars is vital to assess the planet’s potential for harboring life and for providing usable resources for future human exploration. For this reason, "Follow the Water" was the science theme of NASA's Mars Exploration Program (MEP) in the first decade of the 21st century. NASA and ESA missions including 2001 Mars Odyssey, Mars Express, Mars Exploration Rovers (MERs), Mars Reconnaissance Orbiter (MRO), and Mars Phoenix lander have provided information about water's abundance and distribution on Mars.Mars Odyssey, Mars Express, MRO, and Mars Science Lander Curiosity rover are still operating, and discoveries continue to be made.
I am doing a exam in science need help.
What type of energy comes from the motion of tiny particles of matter?
Answer:
here you are
Explanation:
atomic energy
What is the molarity of the resulting solution when 300. mL of a 0.400 M solution is diluted to 800.
mL?
Answer:
0.150M
Explanation:
hope it helps!!!!!!!!!!!!
The molarity of the resulting solution when 300. mL of a 0.400 M solution is diluted to 800 mL is 0.15M.
Molarity is defined as the ratio of the number of moles of solute present in a solution, to the volume of that particular solution in litres.
It is calculated by using the formula
M₁V₁ = M₂V₂
M₁= initial molarity of the solution
V₁ = initial volume of the solution
M₂ = final molarity of the solution
V₂ = final volume of the solution
Given data,
M₁ = 0.400 M (initial molarity)
V₁ = 300 mL (initial volume)
V₂ = 800 mL (final volume)
Substituting the values we get
M₁V₁ = M₂V₂
.4× 300/800 = M₂
Therefore, molarity of the resulting solution = .15
To know more about molarity here
https://brainly.com/question/33791250
#SPJ2
5. How many grams of Br is needed to make 1000.g of a 2.0ppm solution?
Answer:
2.0 × 10⁻³ g
Explanation:
Step 1: Given data
Mass of solution: 1000. g (1.000 kg)Concentration of Br₂: 2.0 ppmStep 2: Calculate the mass of Br₂ required to prepare the solution
The concentration of Br₂ is 2.0 ppm, that is, there are 2.0 mg of Br₂ per kilogram of solution. The mass of Br₂ required to prepare 1.000 kg of solution is:
1.000 kg Solution × 2.0 mg Br₂/1 kg Solution = 2.0 mg
Step 3: Convert the mass to grams
We will use the conversion factor 1 g = 1000 mg.
2.0 mg × 1 g/1000 mg = 2.0 × 10⁻³ g
8. 53.4 mL of a 1.50 M solution of NaCl is on hand, but you need some 0.800 M
solution. How many mL of 0.800 M can you make?
9. A stock solution of 1.00 M NaCl is available. How many milliliters are needed
to make 100.0 mL of 0.750 M
10.2.00 L of 0.800 M NaNO, must be prepared from a solution known to be 1.50
M in concentration. How many mL are required?
PLS answer ASAP!! WILL MARK AS BRAINLYIST!
A gas has a volume of 10 L at 200 K and a pressure of 1.5 atm . What would the volume of the gas be at 300 K and 2atm of pressure ?
Answer:
jeyjeyjetnetney
Explanation:
thmrhmrhmrum
3. Pepsi puts 355 ml of soda in a can. How many drops is this?
Write a mechanism for the conversion of the aldol addition product, 3-hydroxy-3-(4-nitrophenyl)-1-(2-pyridyl)-1-propanone, to the aldol condensation product, (E)-3-(4-nitrophenyl)-1-(2-pyridyl)-1-propenone. Be as complete as possible and show electron flow for all steps.
Solution :
"Aldol" stands for the abbreviation, aldehyde and alcohol. When a ketone or an aldehyde's enolate reacts with the carbonyl of a molecule at the alpha carbon, under the acidic or basic conditions so as to obtained the ketone or β-hydroxy aldehyde, is known as an aldol reaction.
For the conversion of the aldol addition product of a 3-hydroxy-3-(4-nitrophenyl)-1-(2-pyridyl)-1-propanone to an aldol condensation product of (E)-3-(4-nitrophenyl)-1-(2-pyridyl)-1-propenone, the mechanism is given in the diagram a below :
What do you think a mutation is?
The weak base ionization
constant (Kb) for C4H4N2 is
equal to
Answer:
A
Explanation:
The weak base ionization constant (Kb) for [tex]C_{4} H_{4} N_{2}[/tex] is equal to Option A.
Are weak foundations made of ionized?A weak foundation is a base that makes ionize only slightly in an aqueous solution. Remember that a foundation can be defined as an object, which receives a hydrogen ion from another object.
What is the kb of a weak foundation?To obtain an aqueous solution of a weak acid, the dissociation constant is called the acid ionization constant (Ka). Similarly, the constant equilibrium of a weak base reaction with water is the base ionization constant (Kb). In any conjugate acid-base pair, KaKb = Kw.
Learn more about ionization here: brainly.com/question/25676623
#SPJ2
Calculate the percent by mass of the solute in an aqueous solution of 27.2 g ethanol in 250 g of total solution.
Answer:
Explanation:
H
Mass percent can be calculated from the mass of solute in grams divided by the mass of solution multiplied by 100. The percent by mass of the solute in aqueous solution of 27.2 g ethanol in 250 g of total solution 10.88 %.
What is mass percentage?Mass percentage is term used to represent the concentration of a solution. Mathematically mass percent of a component in a mixture is the mass of the component divided by the total mass multiplied by 100.
A solution is made of a solvent and solute. Thus, the total mass of the solution is the sum of mass of solute and mass of the solvent. Here, the solute is ethanol with a mass of 27.2 g. The total mass of solution is 250g.Hence, the mass percent of ethanol can be calculated as follows:
Mass percent of ethanol = mass of ethanol/total mass ×100
= (27.2/250)×100
= 10.88 %.
Hence, the percent by mass of solute ethanol in the total solution is 10.88%.
To find more about mass percent, refer the link below:
https://brainly.com/question/5394922
#SPJ2
Climate indicators are events occurring that identify climate change as more than a change in temperature. What is happening to each event as
the climate changes?
Temperatures are
sea levels are
carbon dioxide levels in the atmosphere are
, and the amount of sea ice is
For the blanks it’s either increasing or decreasing
Answer:
As the climate changes, temperatures are increasing, sea levels are rising, carbon dioxide levels in the atmosphere are increasing, the pH of the ocean is decreasing, and the amount of sea ice is decreasing.
Explanation:
What is the mass in grams of 8.65 mol C8H18?
Answer in standard notation to zero decimal places.
PLEASE HELP THIS IS DUE AT 11:59 AT MIDNIGHT AND IM FREAKING OUT
Answer:
m = 998 g
Explanation:
Hello there!
In this case, according to the definition of the molar mass as the mass of one mole of the compound, it is possible to state the 1 mole of C8H18 has a mass of 114.26 grams; therefore, the mass in 8.65 moles turn out to be:
[tex]m=8.65mol*\frac{114.26g}{1mol}\\\\m=998g[/tex]
In agreement to the notation requirement.
Best regards!
Determine the number of formula units in 48.0 grams of magnesium chloride (MgCl2)
Answer:
3.03 x 10²³ formula units
Explanation:
First we convert 48.0 grams of magnesium chloride into moles, using its molar mass:
48.0 g ÷ 95.21 g/mol = 0.504 mol MgCl₂Then we convert 0.504 moles into formula units, using Avogadro's number:
0.504 mol * 6.023x10²³ formula units/mol = 3.03x10²³ formula unitsOnly 5 minutes to answer!
Why are the weather satellites important on Mars?
Answer:
they can track the weather which can show if it would be posssible to live or have life on mars
Explanation: