The sum of the squares of two sides of a right angle is equal to the square of the hypotenuse
how is the akin of frog similar to a fish
Answer:
Have you ever touched a fish? Most fish will feel a bit rough - due to their scales. Some, like sharks, will feel like sandpaper. Even fish with small, smoother scales will feel a bit like that. Amphibians don’t have scales, and most species will be wet to some degree - they have to keep their skin moist or they’ll die. A few groups, like toads and newts, have rougher skin, which is heavier and thicker, which allows them to retain moisture better away from water.
Functionally, the big thing about amphibian skin is that it is semi-permeable. Amphibians can breathe through their skin - all amphibians can get some oxygen through their skin, but some species of salamanders get all their oxygen that way - they have no lungs or gills. The skin can also allow water in - sort of like a paper towel. The bad thing is that other chemicals can pass through the skin, too - pollutants and other chemicals tend to affect amphibians far more than they do other groups.
Amphibians also shed their skin - fish do not. People don’t tend to see frogs shedding their skin often, though, since they eat it to regain nutrients and other resources in the skin.
Finally, since amphibian skin offers no defense against predators in the way that scales do, and limited barrier against disease the way non-amphibian skin does (shedding helps), the skin of many amphibians contain toxins, and some of them have anti-fungal properties (typically due to symbiotic bacteria). Many species have evolved chemical defenses in the skin, while others have glands that produce toxins that can be secreted outside of the skin.
The skin can withstand dessication more than the fish.
They have moist skin used as respiratory surface during deep sleep / hibernation.
They have moist skin due to secretion of mucus by glands under the skin.
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what is meant by density
Answer:
The degree of compactness of a substance
g aqueous barium hydroxide (ba(oh)2) and nitric acid (hno3) participate in a complete neutralization reaction. in the molecular equation, what are the products
Answer:
Where the products are H2O and Ba(NO3)2
Explanation:
A base, as, barium hydroxide (Ba(OH)2) reacts with an acid (HNO3), producing water (H2O), and the related salt (Ba(NO3)2) in a reaction called neutralization reaction.
The balanced reaction is:
Ba(OH)2 + 2 HNO3 → 2 H2O + Ba(NO3)2
Where the products are H2O and Ba(NO3)2
Which of the following is a reduction half-reaction?
Solution : An oxidation reduction (redox) reaction is a type of chemical reaction that involves a transfer of electrons between tow species an oxidaion reductin reaction is any chemical reaction in which the oxidation number of a molecule atom or ion changes by gaining or losing an electron
Suppose you are using distillation to separate cyclohexane and toluene. The boiling point of cyclohexane is Choose... oC and the boiling point of toluene is Choose... oC. Therefore, the liquid collected first should be Choose... .
Answer:
81°C
111°C
cyclohexane
Explanation:
Distillation is a process of separating two liquids based on differences in Bolling point. For two substances having different boiling points, they are collected as they are converted into vapour, condensed and move down the condenser one after the other.
Since the boiling point of cyclohexane is less than that of toluene, cyclohexane is collected first before toluene.
Starting from (R)-3-methylhex-1-yne as the substrate at the center of your page, draw a reaction map showing the regiochemical and stereochemical outcome or outcomes for each of the following series of reagents. Name each of your products, including stereochemical designations for any chirality centers that are generated.
a. HgSO4, H2SO4, H2O
b. 1. 9-BBN; 2. H2O2, NaOH
c. Br2, CCl4
d. HBr
Solution :
A substrate is defined as the chemical species that are being observed in the chemical reaction where the substrate reacts with a reagent and forms a product. It can also be referred to the surface where some other chemical reactions are performed.
Stereochemistry is defined as the study of relative spatial arrangement of the atoms which forms the structure of the molecules and their respective manipulations.
In the context, the products including the stereochemical designations for any chirality centers starting from the (R)-3-methylhex-1-yne as the substrate are attached below.
# of protons
# of neutrons
# of electrons
Atomic Number
Mass Number
18
17
35
17
37
6
8
6
6
15
Answer:
35
Explanation:
is the answer for your question
I performed an experiment and mixed copper nitrate and potassium iodide. When they reacted, they formed a precipitate, even though solubility rules would not lead one to predict so because potassium nitrate is obviously soluble and so should copper (II) iodide. One can deduce from the formation of a precipitate that copper is reduced. Write a proposed reaction for the oxidation reduction of copper (II) iodide. Justify the choice of the substance that reduces the copper based on experimental evidence. Also, justify the choice using the atomic structure of potassium ion and iodide ion.
Answer:
2Cu2^+ + 2I^- ----> 2Cu^+ + I2
Explanation:
The reaction performed in the experiment is;
2 Cu(NO3)2 + 4 KI → 2 CuI (s) + 4 KNO3 + I2
The iodide ions reduces Cu^2+ to Cu^+ which is insoluble in water hence the precipitate. This is so because iodine is a good oxidizing agent seeing that it requires one electron to fill its outermost shell. Potassium on the other hand is a good reducing agent since it easily looses its one electron.
The oxidation - reduction equation is as follows;
2Cu2^+ + 2e ----> 2Cu^+ reduction half equation
2I^- ----> I2 + 2e. Oxidation half equation
Balanced redox reaction equation;
2Cu2^+ + 2I^- ----> 2Cu^+ + I2
A tank contains isoflurane, an inhaled anesthetic, at a pressure of 0.30 atm and 17.9°C. What is the pressure, in atmospheres, if the gas is warmed to a
temperature of 27.4°C, if n and V do not change?
Explanation:
here's the answer to your question
The pressure of the isoflurane gas at the temperature of 27.4 °C is 0.31 atm.
What is Gay Lussac's law?Gay-Lussac's law states that the pressure of a gas is directly proportional to the absolute temperature when the volume of the gas is kept constant.
Mathematically, Gay Lussca's law can be written as follows:
P/T = k
It is also expressed as the pressure of the gas being directly proportional to temperature.
P ∝ T (where V is constant)
or
[tex]\frac{P_1}{T_1} =\frac{P_2}{T_2}[/tex] ................(1)
Given, the initial pressure and initial temperature of the gas:
P₁ = 0.30 atm
and T₁ = 17.9 °C. = 17.9 + 273 = 290.9 K
The final temperature of gas T₂ = 27.4°C = 27.4 + 273 = 300.4 K
Now, from the equation (1): [tex]P_2=\frac{P_1\times T_2}{T_1}[/tex]
P₂ = (0.30) × (300.4)/290.0
P₂ = 0.31 atm
Therefore, the pressure of the isoflurane at 27.4°C is equal to 0.31 atm.
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A compound made of elements A and B, has a cubic unit cell. There is an A atom at each corner of the cube and an A atom at the center of each face of the cube. There are four B atoms that lie entirely within the unit cell. Based on this information, the empirical formula for the compound is:
Answer:
A₅B₄
Explanation:
Since we have one atom of element A at the center of each face of the unit cell, since the unit cell is a cubic cell, we have 6 faces. Since the atom on the face of the unit cell is shared with another cell, we have half of it in the unit cell is shared So, the number of atoms per face is 1/2 atom/face × 6 faces = 4 atoms on the faces of the unit cell.
Also, we have 1 atom at each corner of the cubic unit cell. Since there are 8 corner in the cubic unit cell. Also, each atom at the corner is shared with 8 unit cells, so we have 1/8 atom per corner. So, the number of atoms per unit cell is 1/8 atom/corner × 8 corners = 1 atoms at the corners of the unit cell.
So, in total we have 4 + 1 = 5 atoms of element A in the unit cell.
Also, there are 4 atoms of element B in the unit cell.
So, the ratio of atoms of element A to element B is 5 : 4.
A:B = 5:4
So, the empirical formula of the compound containing elements A and B is A₅B₄
If the Ksp of NaCl is experimentally determined to be 43.9, then what is the concentration of Na (in M) when it begins to crystallize out of solution
Answer:
6.63 M
Explanation:
NaCl(s) ---> Na^+(aq) + Cl^-(aq)
Given that [Na^+] = [Cl^-] = s
Where s= concentration of the both ions
Ksp = s^2
s= √Ksp
s= √43.9
s= 6.63 M
The concentration of Na (in M) obtained when it begins to crystallize out of solution is 6.63 M
What is solubility of product?The solubility of product (Ksp) is defined as the concentration of products raised to their coefficient coefficients. This is illustrated below:
mX <=> nY + eZ
Ksp = [Y]^n × [Z]^e
Dissociation equationNaCl(aq) → Na⁺(aq) + Cl¯(aq)
Let the concentration of Na⁺ be yLet the concentration of Cl¯ be yHow to determine the concentration of Na⁺ Solubility of product (Ksp) = 43.9Concentration of Cl¯ = yConcentration of Na⁺ = y =?Ksp = [Na⁺] × [Cl¯]
43.9 = y × y
43.9 = y²
Take the square root of both side
y = √43.9
y = 6.63 M
Thus, the concentration of Na⁺ is 6.63 M
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Name the following compound: CH3CH2CH2CH2CH2CH2CCCH3
2-nonene
7-nonyne
2-heptyne
2-nonyne
Finding Nemo??? sorry I really need these points
Answer:
2-nonyne
explanation:
First consider the type of bonds, there are tripple bonds of carbon to carbon, in position 2 from the right.
hence it us alkyn.
There are 9 carbons.
When 1 mole of CO(g) reacts with H2O(l) to form CO2(g) and H2(g) according to the following equation, 2.80 kJ of energy are absorbed. CO(g) + H2O(l)CO2(g) + H2(g) Is this reaction endothermic or exothermic? _________ What is the value of q? kJ
Name this compound?
*Please asap*
Trả lời:3 5-dimethylheptane
Explanation:
Place the following elements in order of decreasing atomic size: lead, phosphorus, oxygen, cesium, barium, and silicon.
Rank from largest to smallest. To rank items as equivalent, overlap them.
Cs, O, P, Si, Ba, Pb
Answer:
Cs> Ba> Pb>Si> P>O
Explanation:
Recall that atomic size decreases across a period and increases down the group.
As we move from Cs to Ba, the atomic size decreases across the period. Lead is larger than silicon since atomic size increases down the group.
Between phosphorus and oxygen, phosphorus is larger than oxygen as you move across the period.
A reaction was performed, and the dichloromethane solvent was dried by adding magnesium sulfate drying agent. When the reaction flask was shaken, it was observed that the magnesium sulfate clumped together at the bottom of the flask. What does this observation indicate
The clumping of magnesium sulfate means that the wrong kind of drying agent have been used for the sample.
What is a drying agent?A drying agent is also referred to as a desiccant. It is a substance that is used to remove moisture from a sample. We must recall that the drying agent to be used must not react with the sample.
Since the magnesium sulfate was found to clump together at the bottom of the flask, it means that the wrong kind of drying agent have been used for the sample.
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Give the change in condition to go from a gas to a solid. Group of answer choices cool or increase pressure cool or reduce pressure increase heat or reduce pressure increase heat or increase pressure none of the above
Answer:
cool or increase pressure
Explanation:
For a gas to form solid. There must be reduced heat and pressure. The deposition of gas into solid occurs through the removal of thermal energy. The air looses thermal energy and changes into solid.Do you think that people decide their destiny, or that their destiny has already been decided and they cannot change ,they only discover it ?
i don't know if this is for school or what. but I believe that your destiny is set out but you do have the power to change it. you decide what path you want to go down with your actions
Question 4
18 g of carbon dioxide contains how many oxygen atoms?
Answer:
4.92×10²³ atoms of oxygen.
Explanation:
We'll begin by calculating the number of mole of oxygen in 1 mole of CO₂. This can be obtained as follow:
1 mole of CO₂ contains 2 mole of oxygen.
1 mole of CO₂ = 12 + (2×16)
= 12 + 32
= 44 g
Thus,
44 g of CO₂ contains 2 moles of oxygen.
Next, we shall determine the number of mole of oxygen in 18 g of CO₂. This can be obtained as follow:
44 g of CO₂ contains 2 moles of oxygen.
Therefore, 18 g of CO₂ will contain
= (18 × 2)/ 44 = 0.818 mole of oxygen.
Finally, we shall determine the number of atoms in 0.818 mole of oxygen. This can be obtained as follow:
From Avogadro's hypothesis,
1 mole = 6.02×10²³ atoms.
Therefore,
0.818 mole = 0.818 × 6.02×10²³ atoms.
0.818 mole of oxygen = 4.92×10²³ atoms.
Thus, 18 g of CO₂ contains 4.92×10²³ atoms of oxygen.
A solution is made by dissolving 0.565 g of potassium nitrate in enough water to make up 250. mL of solution. What is the molarity of this solution?
Please explain and show work.
[tex]\\ \large\sf\longmapsto KNO_3[/tex]
[tex]\\ \large\sf\longmapsto 39u+14u+3(16u)[/tex]
[tex]\\ \large\sf\longmapsto 53u+48u[/tex]
[tex]\\ \large\sf\longmapsto 101u[/tex]
[tex]\\ \large\sf\longmapsto 101g/mol[/tex]
Now
[tex]\boxed{\sf No\:of\:moles=\dfrac{Given\:mass}{Molar\:mass}}[/tex]
[tex]\\ \large\sf\longmapsto No\:of\:moles=\dfrac{0.565}{101}[/tex]
[tex]\\ \large\sf\longmapsto No\:of\:moles=0.005mol[/tex]
We know
[tex]\boxed{\sf Molarity=\dfrac{Moles\:of\:solute}{Vol\:of\:Solution\:in\:L}}[/tex]
[tex]\\ \large\sf\longmapsto Molarity=\dfrac{0.005}{\dfrac{250}{1000}L}[/tex]
[tex]\\ \large\sf\longmapsto Molarity=\dfrac{0.005}{0.250}[/tex]
[tex]\\ \large\sf\longmapsto Molarity=0.02M[/tex]
[tex] \: \: \: \: \: \: \: \: \: [/tex]
Carboxylic acids and alcohols react via dehydration and condensation to produce a/an _______ and water.
Question options:
amine
ether
polymer
ester
Answer:
ester
Explanation:
Carboxylic acids and alcohols react in the presence of strong acid to produce an ester and water. The two carbon chains come together, which is the condensation, and then water is generated, which is dehydration. The resulting compound is an ester.
2FePO4+3 Na2so4--->Fe2(so4) + 2 Na3Po4 if i ise 25grams of iron iii phosphate 18.5 g iton what is my percent yeild?
Answer:
56%
Explanation:
If I use 25 grams of iron (III) phosphate and obtain 18.5 g of iron (III) sulfate, what is my percent yield?
Step 1: Write the balanced equation
2 FePO₄ + 3 Na₂SO₄ ⇒ Fe₂(SO₄)₃ + 2 Na₃PO₄
Step 2: Calculate the theoretical yield of Fe₂(SO₄)₃
The mass ratio of FePO₄ to Fe₂(SO₄)₃ is 301.64:399.88.
25 g FePO₄ × 399.88 g Fe₂(SO₄)₃/301.64 g FePO₄ = 33 g Fe₂(SO₄)₃
Step 3: Calculate the percent yield of Fe₂(SO₄)₃
We will use the following expression.
%yield = (experimental yield/theoretical yield) × 100%
%yield = (18.5 g/33 g) × 100% = 56%
Which combination of reagents used in the indicated order with benzene will give m-nitropropylbenzene? a. 1) CH3CH2CH2Cl/AlCl3, 2) HNO3/H2SO4 b. 1) HNO3/H2SO4, 2) CH3CH2CH2Cl/AlCl3 c. 1) CH3CH2CH2Cl/AlCl3, 2) HNO3/H2SO4, 3) Zn/HCl d. 1) HNO3/H2SO4, 2) CH3CH2CH2Cl/AlCl3, 3) Zn/HCl
Answer:
1) HNO3/H2SO4, 2) CH3CH2CH2Cl/AlCl3
Explanation:
Benzene is a stable aromatic compound hence it undergoes substitution rather than addition reaction.
When benzene undergoes substitution reaction, the substituent introduced into the ring determines the position of the incoming electrophile.
If I want to synthesize m-nitropropylbenzene, I will first carry out the nitration of benzene using HNO3/H2SO4 since the -nitro group is a meta director. This is now followed by Friedel Craft's alkykation using CH3CH2CH2Cl/AlCl3.
Match each land resource to its use.
clay - used to make steel
iron ore - used to make batteries
salt - used to make pottery and tiles
aggregate - used in construction
graphite - used as a flavoring in food
i will give 10 points and brainliest!!!
Answer:
answer in picture
Explanation:
Consider a galvanic (voltaic) cell that has the generic metals X and Y as electrodes. If X is more reactive than Y (that is, X more readily reacts to form a cation than Y does), classify the following descriptions by whether they apply to the X or Y electrode.
i. anode
ii. cathode
iii. electrons in the wire flow toward
iv. electrons in the wire flow away
v. cations from salt bridge flow toward
vi. anions from salt bridge flow toward
vii. gains mass
viii. loses mass
Answer:
X
anode
electrons in the wire flow away
anions from salt bridge flow toward
loses mass
Y
cathode
electrons in the wire flow toward
cations from salt bridge flow toward
gains mass
Explanation:
In a galvanic cell, oxidation occurs at the anode while reduction occurs at the cathode. The metal that is more reactive functions as the anode while the less reactive metal functions as the cathode.
Electrons leave the anode and travel via a wire to the cathode. At the anode cations give up electrons and enter into the solution.
At the cathode, cations pick up electrons and are deposited on the cathode leading to a gain in mass at the cathode.
Positive ions from the salt bridge flow towards the cathode while negative ions from the salt bridge flow towards the anode.
A 10.53 mol sample of krypton gas is maintained in a 0.8006 L container at 299.8 K. What is the pressure in atm calculated using the
van der Waals' equation for Kr gas under these conditions? For Kr, a = 2.318 L'atm/mol and b = 3.978x10²L/mol.
Answer:
-401.06 atm
Explanation:
Applying,
P = (nRT/V-nb)-(an²/V²)............... Equation 1
Where P = Pressure, R = Universal gas constant, V = molar Volume, T = Temperature in Kelvin, a = gas constant a , b = gas constant b, n = numbers of mole
From the question,
Given: T = 299.8 K, V = 0.8006 L, a = 2.318 L.atm/mol, b = 3.978×10²L/mol
Constant: R = 0.0082 atm.dm³/K.mol
Substitute these values into equation 1
P = [(0.0082×299.8×10.53)/(0.8006-(10.53×397.8)]-[(10.53²×2.318/0.8006²)]
P = (25.89/-4188.0334)-(400.995)
P = -0.0618-400.995
P = -401.06 atm
If 50.0 g of sulfuric acid and 40.0 grams of barium chloride are mixed, how many grams of sulfuric acid and how many grams of barium chloride remain after the double replacement reaction is complete?
After the double replacement reaction from mixing 50.0g of sulfuric acid and 40.0 grams of barium chloride is complete, 31.16 grams of sulfuric acid and 0 grams of barium chloride remain.
The equation of the reaction between sulfuric acid and barium chloride is
BaCl₂ + H₂SO₄ → BaSO₄ + 2HCl
From this equation of reaction, it means 1 mole of barium chloride will completely react with 1 mole of sulfuric acid.
From the question, we have 50.0g of sulfuric acid and 40.0 grams of barium chloride.
First, we will determine the number of moles of the sulfuric acid and barium chloride present.
Number of moles is given by the formula
Number of moles = Mass / Molar mass
For sulfuric acid
Mass = 50.0 g
Molar mass = 98.079 g/mol
∴ Number of moles = 50.0 / 98.079
Numbers of moles of sulfuric = 0.509793 mol
For barium chloride
Mass = 40.0 grams
Molar mass of barium chloride = 208.23 g/mol
∴ Number of moles = 40.0 / 208.23
Number of moles of barium chloride = 0.192095 mol
Since the number of moles of sulfuric acid is more than that of barium chloride, then the limiting reagent is barium chloride and the excess reagent is sulfuric acid
NOTE: A limiting reagent is the reactant that is completely used up in a reaction, and it determines when the reaction stops.
Hence, barium chloride will be used up during the reaction (that is, 0 grams will remain after the reaction is complete).
For the mass of sulfuric acid that will remain,
First, we will determine the number of mole that will remain.
Since 1 mole of barium chloride completely reacts with 1 mole of sulfuric acid, then 0.192095 mol of barium chloride will react with 0.192095 mol of sulfuric acid.
∴ The remaining number moles of sulfuric acid = 0.509793 mol - 0.192095 mol
The remaining number moles of sulfuric acid = 0.317698 mol
Then, from
Mass = Number of moles × Molar mass
Mass = 0.317698 mol ×98.079 g/mol
Mass = 31. 1595 gram
Mass ≅ 31.16 grams
∴ 31.16 grams remains after the reaction is complete.
Hence, 31.16 grams of sulfuric acid and 0 grams of barium chloride remain after the double replacement reaction is complete.
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Ladkiyoooooo aaa jaooo♡♥︎♡
Jaldiiiii karo na yaaaar
Answer:
kjajjahahayq :/
Explanation:
a sbywsbgv usnwbhx hg xw nx hb gs
Answer:
Don´t Post Irrelevant Questions!!Explanation:Conversion Problem (show all work):
1. A patient required 3.0 pints of blood during surgery. How many liters does this correspond
to? Show all work. Use conversion factors available in the text or the exam packet. (4)
1.42liters, which is equivalent to 3pints, of blood is required for the surgery
Pints is a unit of measurement for volume in the United States. However, it can be converted to litres using the following equation:1 US pint = 0.473 liters
Hence, according to this question which states that a patient required 3.0 pints of blood during surgery. This means that the patient required:3 × 0.473
= 1.419 liters of blood for the surgery
1.42liters, which is equivalent to 3pints, of blood is required for the surgeryLearn more at: https://brainly.com/question/24168664
Which gas has the highest diffusing rate between nitrogen , oxygen , hydrogen and chlorine
Answer:
hydrogen
Explanation:
The gas with the least molecular weight effuses the fastest (Graham's Law). Hence, H gas has a higher rate of diffusion compared to N, O, and Cl.
So, Cl is the slowest when it comes to the rate of diffusion, because it has the highest molecular weight.
