18) Calculate the molarity
of a solution if 42 grams
of NaCl is dissolved in
780 mL of water.
a .56 M
b 92 M
c 1.1 M
d 54M
Answer:
B. 0.92 M
Explanation:
Molarity of a solution = number of moles (n) ÷ volume (V)
According to the information provided in this question;
mass of NaCl = 42g
Volume of water = 780mL
Using mole = mass/molar mass
Molar mass of NaCl = 23 + 35.5 = 58.5g/mol
mole = 42/58.5
mole (n) = 0.72mol
Volume (V) = 780 mL = 780/1000 = 0.780 L
Hence, molarity = n/V
Molarity = 0.72/0.780
Molarity = 0.923 M
Using two ______________ of wire wrapped around an _____________ core produces an ______________ voltage and an _______________ voltage.
Answer:
Using two coils of wire wrapped around an iron core produces an input voltage and output voltage.
Explanation:
Ca + AgCl (Single Replacement Reactions) PLEASE HELP
Answer:
2Ag + CaCl2
Explanation:
https://en.intl.chemicalaid.com/tools/equationbalancer.php?equation=Ca+%2B+AgCl+%3D+Ag+%2B+CaCl2 use that website for chemistry
What is the pH of a solution in which [OH-] = 1.0 x 10-2 M
Answer:
12
Explanation:
pOH = -log(1.0 x 10^-2) = 2
pH = 14 - pOH
pH = 14 - 2 = 12
What is an example of a microorganism acting in a harmful way?
Answer:
bacteria spoiling food
hope this helps
have a good day :)
Explanation:
What is the wavelength of spectral line resulted from the electron transition from n=3 to n=2 in a hydrogen atom.
Answer:
[tex]\lambda=6.56x10^{-7}m[/tex]
Explanation:
Hello there!
In this case, it possible to use the Rydberg equation in order to calculate the wavelength for this transition from n=3 to n=2 as shown below:
[tex]\frac{1}{\lambda} =R_H(\frac{1}{n_f^2}-\frac{1}{n_i^2} )[/tex]
Thus, we plug in the corresponding energy levels and the Rydberg constant to obtain:
[tex]\frac{1}{\lambda} =10973731.6m^{-1}(\frac{1}{2^2}-\frac{1}{3^2} )\\\\\frac{1}{\lambda} =1524129.4m^{-1}\\\\\lambda=\frac{1}{1524129.4m^{-1}} \\\\\lambda=6.56x10^{-7}m[/tex]
Best regards!
how do you make a potion of slow falling
Answer:
So you can make it longer by putting in some redstone. And this will give you a potion that will last for 4 minutes. Alright we're done it's got 4 minute slow falling potions.
Explanation:
Answer:
Ok, to make a slow falling potion, you need 1 water bottle, 1 nether wart, and 1 fantom membrane.
Explanation:
hope I could help, lmk if I did!
What effect does an increase in carbon dioxide (CO 2 ) have on the concentration of hydrogen ions (H^ + ) in the blood?
Answer:
As the level of carbon dioxide in the blood increases, more H+ is produced and the pH decreases. This increase in carbon dioxide and subsequent decrease in pH reduce the affinity of hemoglobin for oxygen. The oxygen dissociates from the Hb molecule, shifting the oxygen dissociation curve to the right.
A una mezcla de 300g, formada con 60% P/P de Hierro y 40% P/P de Arena, se le adicionan 135g de Cobre y 2,77g de Aluminio. ¿Cuál es la concentración final P/P de cada uno de los componentes?
Answer:
[tex]\%P/P_{hierro}=41.1\%\\\\\%P/P_{arena}=24.4\%\\\\\%P/P_{cobre}=30.8\%\\\\\%P/P_{aluminio}=0.6\%[/tex]
Explanation:
¡Hola!
En este caso, dado que estamos tratando con problem sobre porcentaje peso/peso de hierro, arena, cobre y aluminio, primero debemos calcular la masa inicial de estos dos primeros en la mezcla original de acuerdo con:
[tex]m_{hierro}=300g*0.60=180g\\\\m_{arena}=300*0.40=120g[/tex]
Ahora si podemos calcular la masa de la mezcla final como la suma de las masas de todos los constituyentes de la mezcla:
[tex]m_T=180g+120g+135g+2.77g=437.77g[/tex]
Finalmente, podemos calcular los porcentajes P/P como se muestra a continuación:
[tex]\%P/P_{hierro}=\frac{180g}{437.77g} *100\%=41.1\%\\\\\%P/P_{arena}=\frac{120g}{437.77g} *100\%=24.4\%\\\\\%P/P_{cobre}=\frac{135g}{437.77g} *100\%=30.8\%\\\\\%P/P_{aluminio}=\frac{g}{437.77g} *100\%=0.6\%[/tex]
¡Saludos!
Belle’s grandfather lives in a region where the temperature drops below 0°F at night. When Belle visited her grandfather, they hiked up a hill. Belle noticed that a lot of rocks had cracks in them. She also found quite a few rocks that had split into pieces. What most likely caused the rocks in this region to weather?
Answer : Normally all molecular motions seizes at 0k which is -272oC so the temperature can't go below that
Explanation:
But, the rocks cracked because of too much expansion. Generally at night, water can be found within rocks which then evaporates during the day. And when water is cold or freezed it expands. So, as the water in the rock expands it causes an increase in size until a certain level where it can no more expand, it cracks.What causes the split of the rock is due to the expansion of water as it freezes
Answer:The answer is B
Explanation:
A gas is in a container with an initial volume of 2.50L, initial pressure of 1.34 atm, and initial temperature of 308 K. What would be the pressure if the gas was heated to 373 K and the volume decreased to 1.90 L? *Hint use the Combined Gas Law.
Answer: The pressure is 2.14 atm if the gas was heated to 373 K and the volume decreased to 1.90 L.
Explanation:
Given: [tex]V_{1} = 2.50 L[/tex], [tex]P_{1} = 1.34 atm[/tex], [tex]T_{1} = 308 K[/tex]
[tex]P_{2} = ?[/tex] , [tex]V_{2} = 1.90 L[/tex], [tex]T_{1} = 373 K[/tex]
Formula used to calculate the final pressure is as follows.
[tex]\frac{P_{1}V_{1}}{T_{1}} = \frac{P_{2}V_{2}}{T_{2}}[/tex]
Substitute the values into above formula as follows.
[tex]\frac{P_{1}V_{1}}{T_{1}} = \frac{P_{2}V_{2}}{T_{2}}\\\frac{1.34 atm \times 2.50 L}{308 K} = \frac{P_{2} \times 1.90 L}{373 K}\\P_{2} = \frac{1.34 atm \times 2.50 L \times 373}{308 K \times 1.90 L}\\= 2.14 atm[/tex]
Thus, we can conclude that the pressure is 2.14 atm if the gas was heated to 373 K and the volume decreased to 1.90 L.
Which functional group does the molecule below contain
H
H-C-C
H
H
A. Carbonyl
B. Hydroxyl
Amino
D. Ether
The functional group to which the molecule belongs is the carbonyl group.
What is a functional group?A functional group refers to an atom, group of atoms or bond which is responsible for the chemical reactivity of a particular homologous series.
From the image of the molecule that has been shown in the question, the functional group to which the molecule belongs is the carbonyl group.
Learn more about carbonyl:https://brainly.com/question/21440134
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Answer:
A
Explanation:
got it right in app filler filler filler filler
ALEX RODE HIS BIKE
60 km in 4 Hours. How FAST WAS HE GOING
Answer:
15 km/hour
Explanation:
You need to find how fast he was going per hour.
Answer: 15
Divide. 60 ÷ 4
This gives us 15. So, Alex was going 15 mph
What is the new pressure?
kPa
Answer:
1 kPa = 760/101.325 = 7.5 mmHg; atm = atmosphere; kPa = kilo Pascal; mmHg = millimetres of mercury.
Answer:
5,000
Explanation:
ed2021
¿Cual es porcentaje de una solucion que contiene 10g de sal disueltos en 500 mL de solución?
Answer:
0.02 g/ml
Explanation:
si dividimos 10 con 500, es decir, 10/500, obtenemos 0.02. Las unidades serán g / ml.
Which daughter element is produced from the beta decay of 145/56 Ba?
The daughter element is produced from the beta decay of ¹⁴⁵₅₆Ba is ¹⁴⁵₅₇La.
What are beta particles?A beta particle is emitted from the nucleus of an atom during radioactive decay. The electron, however, occupies regions outside the nucleus of an atom.
Beta particle has no mass and minus charge on itself.
Radioactive decay equation for the Barium is shown as follow:
¹⁴⁵₅₆Ba → ¹⁴⁵₅₇La + °₋₁β
The daughter element which is produced from the from reaction is Lanthanum.
Hence, ¹⁴⁵₅₇La is the daughter element.
To know more about beta decay, visit the below link:
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explain two ways that bills penguin toy is similar to the water cycle
All the water on the earth is the same water that has been here since
BRAINLISTAll the water on the planet is the identical water that has been here since Penguins preen their feathers continually.
What is the water cycle?
Feathers must be defended in prime condition to provide insulation and waterproofing.
Penguins groom with their bills. A gland around the bottom of the tail secretes oil that the penguin distributes throughout its feathers.
Penguins preen for several minutes in the water by stroking their bodies with their flippers while turning and twisting.
Penguins preen to maintain their feathers in head circumstances and are waterproof. On a well-groomed penguin, moisture rarely touches the skin.
Find more information about water cycle here:
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A 26.0 g sample of HCl is dissolved using 1.00 L of water. Calculate the
molarity of this solution. (HCI molar mass: 36.0 g/mol)
Answer:
[tex]\boxed {\boxed {\sf molarity \approx 0.722 \ M \ HCl}}[/tex]
Explanation:
Molarity is the concentration measurement equal to moles per liter.
[tex]molarity=\frac{moles}{liters}[/tex]
We have 26.0 grams of HCl and 1.00 liters of water. We must convert grams of HCl to moles.
To convert from grams to moles, the molar mass is used. Usually we find these values on the Periodic Table, but they are already provided. The molar mass of hydrochloric acid is 36.0 grams per mole. Use this number as a ratio.
[tex]\frac {36.0 \ g \ HCl}{ 1 \ mol \ HCl}[/tex]
Multiply by the given number of grams: 26.0
[tex]26.0 \ g \ HCl *\frac {36.0 \ g \ HCl}{ 1 \ mol \ HCl}[/tex]
Flip the ratio so the grams of hydrochloric acid cancel.
[tex]26.0 \ g \ HCl *\frac {1 \ mol \ HCl}{ 36.0 \ g \ HCl}[/tex]
[tex]26.0 *\frac {1 \ mol \ HCl}{ 36.0 }[/tex]
[tex]\frac {26.0}{ 36.0 } \ mol \ HCl = 0.72222222222 \ mol \ HCl[/tex]
Now we know the moles and liters.
0.72222222222 mol HCl 1.00 LSubstitute these values into the molarity formula.
[tex]molarity = \frac {0.72222222222 \ mol \ HCl}{1.00 \ L }[/tex]
[tex]molarity = 0.72222222222 \ mol \ HCl/L[/tex]
The original measurements of grams and liters have 3 significant figures, so our answer must have the same. For the number we calculated, that is the thousandth place.
0.72222222222The 2 tells us to leave the 2 in the thousandth place.
[tex]molarity \approx 0.722 \ mol \ HCl/ L[/tex]
1 mole per liter is equal to 1 molar, or M. Change the units.
[tex]molarity \approx 0.722 \ M \ HCl[/tex]
The molarity of this solution is approximately 0.722 M HCl
Observations lead to questions. Good scientific questions need to be ___________.
straightforward
testable
inferred
spontaneous
Answer:
I think the answer would be 'testable'.
What would you predict to be the valence number and oxidation number of tin?
Answer:
Tin exists in two oxidation states, +4 and +2. Elemental tin is readily oxidized to the dipositive ion in acidic solution, but this Sn2+ ion is converted to the Sn4+ ion by many mild oxidizing agents, including elemental oxygen. Oxidation under alkaline conditions normally gives the tetrapositive (Sn4+) state.
which detail about globalr clusters does photograhp on page 1 mke clear
Answer:
Globular clusters are densely packed collections of ancient stars. Roughly spherical in shape, they contain hundreds of thousands, and sometimes millions, of stars. Studying them helps astronomers estimate the age of the universe or figure out where the center of a galaxy lies.
Explanation:
what color does a green objcet appear under red light
Answer:
black??
Explanation:
After getting a cut, you should wash it, even though it hurts. Why is it important to do this?
Answer: It is important to wash it becasue that way you can disinfect the cut and protect the cut from any infections.
Answer:
This will reduce the risk of infection and help stop the bleeding. It gets rid of the bacteria that may have been there. But, it is very important to disinfect it and clean it properly after the bleeding stops.
Explain how the iron pipes change into rust?
Light travels one million times faster than sound. How long would light take to travel from one hill to the other?
Answer:
ZOOM PLZ COME WE R BORED
MEETING ID 798 4170 2552
PASSWORD:XCNeV3
Explanation:
I’m to lazy can anyone help me please
Answer: what do i have to do to help.. ;-; like i need instructions and why are the words coverd off black??
;-;
Explanation:
What is the mass of 8.83 x 10^23 formula units of Iron (III) oxide, Fe2O3?
Answer:
234.68g
Explanation:
We understood from Avogadro's hypothesis that 1mole of any substance contains 6.02x10^23 atoms. Therefore, 1mole of Fe2O3 also contains 6.02x10^23 atoms
1 mole of Fe2O3 = (56x2) + (16x3) = 112 + 48 = 160g
Now, if 160g of Fe2O3 contains 6.02x10^23 atoms,
Therefore Xg of Fe2O3 will contain 8.83×10^23 atoms i.e
Xg of Fe2O3 = (160x8.83×10^23)/6.02x10^23 = 234.68g
A solution is prepared by dissolving 150. grams of NaCl in 500 milliliters of water. What is the
molarity of the solution?
Answer:
Explanation:
The answer should be .00500M
The molarity of the solution is = 5.12M
Molarity of the solutionThe molarity of a solution is the measures the number of moles of a solute per liter of a solution.
Molarity = moles solute/Liter solution
Molar mass of sodium (Na) = 23g
Molar mass of chlorine (Cl) = 35.5g
Molar mass of NaCl = 23 + 35.5 = 58.5g/mol
To calculate the quantity of moles in 150g of NaCl,
1mol = 58.5g
xmol = 150g
Cross multiply,
xmol= 150×1/58.5
= 2.56mol
To convert 500mL to Liters,
500/1000 = 0.5 Liters
Substituting into the equation, Molarity = moles solute/Liter solution
Molarity= 2.56/ 0.5 = 5.12M
Learn more about molarity here:
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an example of no chemical reaction occurring
in gizmos
Answer:
Hydrogen + Helium
Explanation:
No reaction occurs
Help please :<
I just need the answer for this as quickly as possible.
Answer:
I think its the 3th one
Explanation: