How many mL of 0.013 M potassium hydroxide are required to reach the equivalence point in the titration of 75 mL 0.166 M hydrocyanic acid?
Answer:
957.7mL
Explanation:
Using the formula below;
CaVa = CbVb
Where;
Ca = concentration of acid (M)
Va = volume of acid (mL)
Cb = concentration of base (M)
Vb = volume of base (mL)
According to the information provided in this question:
Ca = 0.166 M
Cb = 0.013 M
Va = 75mL
Vb = ?
Using CaVa = CbVb
0.166 × 75 = 0.013 × Vb
12.45 = 0.013Vb
Vb =12.45/0.013
Vb = 957.7mL
why elements with more than 20 protons always have a more neutrons than protons?
Answer:
Elements that have atomic numbers from 20 to 83 are heavy elements, therefore the ratio is different. The ratio is 1.5:1, the reason for this difference is because of the repulsive force between protons: the stronger the repulsion force, the more neutrons are needed to stabilize the nuclei.
A teacher brings in a cup of iced water and asks students to discuss if the system is exothermic or endothermic . Aida states the system is exothermic , while Alexander states the system is endothermic .
Answer:
C
Explanation:
In thermodynamics, a exothermic system looses heat to the surroundings while an endothermic system absorbs heat from the surroundings.
A system is a part the universe marked off by a specified boundary. The contents of the cup constitutes the system in this case.
The region of space outside the system is called the surroundings. Hence everything outside the cup constitutes the surroundings.
There are on average 43 g of sugar and 355 mL can of soda please calculate the molarity of sugar in the can of soda the molar mass of sugar is 342.2 g/mol
Explanation:
Given :
Amount of solute - sucrose (C12H22O11) = 41 g
Amount of solvent -soda = 355-mL
Molarity of the solution with respect to sucrose= ?
Molarity(M) is a unit of concentration measuring the number of moles of a solute per liter of solution. The SI unit of molarity is mol/L.
Formula to find the molarity of solution :
Molarity =
Amount of solvent is given in mL, let’s convert to L :
1 L = 1000 mL
Therefore, 355 mL in L will be :
= 0.355 L
We have the amount of solute in g, let’s calculate the number of moles first :
Number of moles (n) =
Molar mass of C12H22O11 = 342.29 g/mol.
Therefore, n =
= 0.119 moles.
Helppppp plz ASAP DON’T GUESS
Explanation:
A B C D isme koyi ans hain doond lo
tolong saya jawab yahhh
(i) Liang - liang stoma lebih banyak di bahagian bawah daun berbanding di bahagian atas permukaan daun.
(ii) Struktur X berfungsi mangawal pembukaan dan penutupan liang stoma
H2SO4 +HI → __ H2S+12 +H2O balance the equation
Answer:
H2SO4 + 8HI → H2S + 4I2 + 4H2O
How does light demonstrate quantization?
A. The velocity of a light wave has a direction as well as speed.
B. The wavelength of light increases as the frequency decreases.
C. The frequency of light increases as energy increases.
D. The energy in light waves comes in units called photons.
Answer:
D. The energy in light waves comes in units called photons.
Explanation:
its known as quatum theory
Which statement best describes wave-particle duality as it applies to electrons?
A. The electrons present in radio waves and microwaves act more like particles than waves.
B. Electrons are particles that emit waves of radiation when they move from higher energy levels to lower energy levels.
с.Electron clouds can be understood as clumps of particles held near one another by wave forces.
D.Electrons can be modeled as waves in some situations and as particles in other situations.
Answer:
D es pero que te ayude amigo
What point A on the phase diagram called?
liquid
(374°C/218 atm)
A
solid
pressure (atm)
gas
temperature (°C)
OA.
the melting point
OB.
the boiling point
Ос.
the freezing point
OD
the critical point
OE.
the triple point
Answer:
D) the critical point
Explanation:
Point A is the critical point in phase diagram. This is the highest temperature and pressure at which a pure material can exist in vapor/liquid equilibrium. Pretty cool!
Some foods undergo sterilization in order to kill bacteria living in and on the
food. What type of radiation is used in sterilization to kill bacteria?
A. Gamma
B. Alpha
C. Beta
D. Fission
Answer:
A: Gamma
Gamma rays have enough energy to kill bacteria
State the method you will use to separate the following substances. (a) calcium carbonate from table salt (b) iodine from sodium chloride (c) table salt from seawater (d) sugar from sugar solution (e) pure water from sewage water (f) ethanol from beer (g) yellow dye from durian ice cream
Answer:
https://www.meritnation.com :)I HOPE IT'S HELP
Answer: There are many forms of table salt: coarse salt, refined salt, iodized salt. It is a crystalline solid, white to very pale pink or gray in color, obtained from seawater or salt deposits. Salt obtained from seawater has crystals that are smaller or larger than rock salt. In nature, table salt consists mainly of sodium chloride (NaCl), but also a few other minerals (trace minerals). Table salt obtained from rock salt may appear more gray because of traces of trace minerals. Table salt is necessary for the survival of all living organisms, including humans. Table salt is involved in regulating the body's water content (liquid balance).
Read the following reactions. Reaction 1: CaO(s) + CO2(g) → CaCO3(s) Reaction 2: H2O(g) → H2O(l) Which reaction leads to an increase in entropy? Only Reaction 1 Only Reaction 2 Both Reaction 1 and 2 Neither Reaction 1 nor 2
Answer: In the given reactions neither reaction 1 nor 2 reaction leads to an increase in entropy.
Explanation:
The degree of randomness present in the molecules of a substance is called entropy.
In gases, molecules are held by weak forces due to which they move apart from each other. Hence, they have high entropy.
In liquids, molecules are a little close to each other so they have less entropy than gases.
In solids, molecules are tightly held together so they have least or negligible entropy.
As reaction 1 is [tex]CaO(s) + CO_{2}(g) \rightarrow CaCO_{3}(s)[/tex] and it shows that product is in solid state. Therefore, entropy is decreasing.
As reaction 2 is [tex]H_{2}O(g) \rightarrow H_{2}O(l)[/tex] and it shows that gas is converted into liquid. Therefore, entropy is also decreasing here.
Thus, we can conclude that in the given reactions neither reaction 1 nor 2 reaction leads to an increase in entropy.
Answer: Neither Reaction 1 nor 2
Explanation:
What exacerbates the heat waves?
Answer:
A heatwave occurs when a system of high atmospheric pressure moves into an area and lasts two or more days.
Explanation:
In such a high-pressure system, air from upper levels of our atmosphere is pulled toward the ground, where it becomes compressed and increases in temperature.
The temperature of a sample of liquid water changes from 50°C to 30°C. Which statement best explains the change
that must happen at the molecular level?
The molecules move more quickly and their average kinetic energy increases
The molecules move more bowly and their average kinetic energy decreases
The molecules move more quickly and their average kinetic energy decreases
The molecules move more slowly and their average kinetic energy increases.
Answer:
The molecules move slower than the temp of 50°c and their average kinetic energy decreases.
Explanation:
kinetic energy cannot increase as temperature is reduced. molecules will still move with reduced motion.
Standardization of a Borax solution (Na2B4O7). You are given a 1.044 M solution of H2SO4. It takes 2.63 mL of this H2SO4 to reach the end point. Knowing it takes 1 H2SO4 to neutralize 2 Na2B4O7, what was the concentration of this Borax solution?
The question is incomplete, the complete question is:
Standardization of a Borax solution (Na2B4O7). A student titrates a 20.00 mL sample of an aqueous borax solution with 1.044 M H2SO4. It takes 2.63 mL of acid to reach the equivalence point. Knowing it takes 1 H2SO4 to neutralize 2 Na2B4O7, what was the concentration of this Borax solution?
Answer: The concentration of borax solution is 0.069 M.
Explanation:
To calculate the concentration of borax solution, the formula used is:
[tex]n_1C_1V_1=n_2C_2V_2[/tex] ....(1)
where,
[tex]n_1, C_1\text{ and }V_1[/tex] are the n-factor, concentration and volume of sulfuric acid
[tex]n_2,C_2\text{ and }V_2[/tex] are the n-factor, concentration and volume of borax solution.
We are given:
[tex]n_1=1\\C_1=1.044M\\V_1=2.63mL\\n_2=2\\C_2=?M\\V_2=20mL[/tex]
Putting values in equation 1, we get:
[tex]1\times 1.044\times 2.63=2\times C_2\times 20\\\\C_2=\frac{1\times 1.044\times 2.63}{2\times 20}\\\\C_2=0.069M[/tex]
Hence, the concentration of borax solution is 0.069 M.
List two possible steps where impurities may be gained, which would appear to be an increase in copper
yield (why you may get more than 100% of the copper back at the end). Be specific about the steps and
how they might add impurities.
Answer:
i) During washing
ii) During Measurement
Explanation:
The two possible steps are :
i) During washing : during the washing method the residue may be not completely dried out and this residue ( water) will add up to the final product ( copper yield ) and this kind of error is called human error.
ii) During measurement : If the weighing instrument is faulty there might be addition in value of the final copper yield which will see the final yield value > 100% . this error occurs when the initial value and final value is been weighed
The atom of element has 25 electrons and 30 neutrons write down its atomic number and mass number.
Answer:
Atomic number = 25 protons
Mass number = ( 25 + 30 ) = 55
Hello Everyone ✌
hw r y'all doin
Pls answer the below questions
What is Malleability
What is ductility
What is Sonorous
Answer:
Malleability describes the property of a metal's ability to be distorted below compression. It is a physical property of metals by which they can be hammered, shaped and rolled into a very thin sheet without rupturing. A malleable fabric could be planate by blow or rolling.
Explanation:
Ductility is the property of a solid, like a metal, to deform under a tensile stress (force). So if you pull on two ends of a metal wire or bar, and it “stretches” you have a ductile substance. Though I must caution that you don't confuse the definition of ductile to mean elastic. They are not synonyms. It is the opposite of brittle. When a ductile item breaks, it is after necking, where the diameter of the wire in question reduces as the length elongated. A brittle, or non-ductile material simple tears apart in a sharp and quick fashion with little to no visible necking taking place.
sonorous: producing sound (as when struck)
PLZ HELP!!! QUESTIONS ARE BELOW!!! :D PLZ COMPLETELY ANSWER THE QUESTIONS WITH A GOOD ANSWER :)
Answer: sorry its lagging i hope this help fore 18.. =D
Explanation:
n,s is repeating the cycle of the inside
Answer/Explanation:
18, a,
I believe the n, and s represents North, South, or just the way the arrows are rotating repeatedly.
18, b,
The phenomenon re-occurring shows the alignment of magnetic dipoles with in a magnet, like inside. The arrows show a direction in the line with an external magnetic field in a way that it can produce its own magnetic fields that seem to travel from North to the South.
18, c,
Incorrect. Refrigerator magnets have multiple layers of magnification, they use opposite polarities to stay this way. If he puts the magnet sideways it may stick to the fridge
~ LadyBrain
Which of the following would be expected to have the highest viscosity? CH3CH2OH, HOCH2OH, CH3CH2CH3
О НОСН2ОН
O They are all the same.
О СН3СН2ОН
O CH3CH2CH3
Answer: Out of the given options [tex]HOCH_{2}OH[/tex] is expected to have the highest viscosity.
Explanation:
The resistance occurred in the flow of a liquid substance is called viscosity.
More stronger is the intermolecular forces present in a substance more will be its resistance in its flow. Hence, more will be its viscosity.
For example, [tex]HOCH_{2}OH[/tex] has strong intermolecular hydrogen bonding than the one's present in [tex]CH_{3}CH_{2}OH[/tex] and [tex]CH_{3}CH_{2}CH_{3}[/tex]. This is because two-OH groups are present over here.
Thus, we can conclude that out of the given options [tex]HOCH_{2}OH[/tex] is expected to have the highest viscosity.
Identify which of the following statements about the isotopes of an element is correct.
A. They have the same electron configuration.
B. They have the same mass number.
C. They have the same numbers of protons and neutrons in the nucleus.
D. They have more protons than neutrons.
Answer:
A
Explanation:
because B is wrong as it doesn't have the same mass number. C is wrong as it has different number of neutrons. D is wrong as it has more neutrons than protons.
Una muestra de 2,5000 (g) de piedra caliza, se disuelve y se precipita el Calcio como oxalato de Calcio (CaC2O4), este precipitado se calcina transformándose en Carbonato de Calcio (CaCO3). El peso de este compuesto es de 1,2093 (g). Calcular el % de Calcio en la muestra
Answer:
[tex]\%Ca=19.378\%[/tex]
Explanation:
¡Hola!
En este caso, basado en la información dada, es posible conocer la masa de calcio en carbonato de calcio, que de hecho es la misma en la muestra, al utilizar el siguiente esquema de cálculo:
[tex]m_{Ca}=1,2093gCaCO_3*\frac{1molCaCO_3}{100.1gCaCO_3}*\frac{1molCa}{1molCaCO_3}*\frac{40.1gCa}{1molCa}\\\\m_{Ca}=0.48444gCa[/tex]
Finalmente, calculamos el porcentaje requerido como sigue:
[tex]\% Ca=\frac{0.48444g}{2.5000g} *100\%\\\\\%Ca=19.378\%[/tex]
¡Saludos!
What BEST describes these three molecules?
If one of the reactants in a reaction us Na2O, what is known about the products?
Ok here's the deal
the answer is A: The products will contain exactly 2 Na atoms and 1 O atom.
Explanation:
thank me later space-ex kids
How many grams are in 36.2 moles of Iron (I) fluoride?
Answer:
4084.808 grams (SigFigs: 4085 grams)
Explanation:
The molar mass of Iron fluoride is 112.84 g/mol.
To calculate the mass, multiply the molar mass by the number of moles.
36.2 mol * 112.84 g/mol = 4084.808 g
Convert to Sigfigs (if necessary):
4085 g
Answer:
The person above is correct
Explanation:
A neutral atom has 37 electrons. How many protons does the
atom have?
a more than 37 protons
bless than 37 protons
C exactly 37 protons
d it is impossible to know without more information
Answer:
It's answer is c) exactly 37 protons
Answer:
C) , Exactly 37 protons.
Explanation:
Remember the electrons have a negative charge, so to make a atom with 37 electrons neutral, you will need the same amount of the opposite type. That means you need 37 protons.
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c) Current cannot flow
Reason: Because the switch is not closed.
Answer:
current can't flow
Explanation:
by the way of explanation it is open circuit in which the current flow whereas in closed circuit the current flow.
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it will be too much help for me.
When a catalyst is added to a chemical reaction it provides a new reaction pathway that results in a different
Answer: That results in a different ALTERNATE pathway which has a LOWER ACTIVATION ENERGY.
Explanation:
There are many factors that affects a chemical reaction, these include'
--> surface area
--> concentration,
--> temperature,
--> pressure and
--> presence of CATALYST.
A CATALYST is defined as the substance that has the ability to alter the rate of a chemical reaction. Many reaction very slowly when left alone, but become faster when other substances are added. Such substances that merely alter the rate of reactions but do not take part in the reactions are called CATALYSTS.
Activation energy is defined as the energy barrier that must be overcome before a reaction takes place. A catalyst is able to increase the rate of a chemical reaction by decreasing the activation energy of the chemical system.
A catalyst provides an ALTERNATE PATHWAY for the reaction that has a LOWER ACTIVATION ENERGY. When activation energy is lower, more reactant particles have enough energy to react, so the reaction occurs faster.
please i need help ……
Answer:
H2
Explanation:
(l) means liquid
(s) means solid
(g) means gaseous
I hope this helped [:
