Need some help with these problems


b. a 0.5 M solution containing 250 g of manganese (II) chloride (MnCl2)
c. a 0.4 M solution containing 290 g of aluminum nitrate (Al(NO3)3)

Answers

Answer 1

complete question:

Calculate the volume of each solution, in liters.

b. a 0.5 M solution containing 250 g of manganese (II) chloride (MnCl₂)

c. a 0.4 M solution containing 290 g of aluminum nitrate (Al(NO₃)₃)

Answer:

b. L ≈ 4.00 litres

c. L ≈ 3.4 litres

Explanation:

Molarity is the number of moles of solute per litre of solution. Together a solute and a solvent makes a solution. The formula for molarity can be represented below

M = number of moles of the solute(mol)/L

where

M = molarity

mol = number of moles of the solute

L = litre of the solution.

Therefore ,

The volume of each solution can be computed below

b. a 0.5 M solution containing 250 g of manganese (II) chloride (MnCl₂)

M = number of moles of the solute(mol)/L

number of moles of MnCl₂ = mass/molar mass

molar mass of MnCl₂ = 55 + 71 = 126 g/mol

number of moles of MnCl₂ = 250/126

number of moles of MnCl₂ = 1.9841 moles

0.5 = 1.9841/L

cross multiply

0.5L = 1.9841

L = 1.9841/0.5

L = 3.97

L ≈ 4.00 litres

c. a 0.4 M solution containing 290 g of aluminum nitrate Al(NO₃)₃

M = number of moles of the solute(mol)/L

number of moles = mass/molar mass

molar mass of Al(NO₃)₃ = 27 + 14 × 3 + 48 × 3 = 27 + 42 + 144 = 213

number of moles = 290/213 = 1.3615 moles

M = number of moles of the solute(mol)/L

0.4 =  1.3615/L

cross multiply

0.4L = 1.3615

divide both sides by 0.4

L = 1.3615/0.4

L = 3.4 litres


Related Questions

What is the coefficient of MnO2when you balance the equation for this redox reaction? KCN( aq) + KMnO4( aq) + H2O( l) → KCNO( aq) + MnO2( s) + KOH( aq)

Answers

Answer:

2MnO2 (s)

Explanation:

3KCN(aq) + 2KMnO4(aq) + 1H2O(l) → 3KCNO(aq) + 2MnO2(s) + 2KOH(aq)

Reactants:

K: 5

C: 3

N: 3

Mn: 2

O: 9

H: 2

Products:

K: 5

C: 3

N: 3

Mn: 2

O: 9

H: 2

PLEASE HELP!!!!!!!!!
The pressure in an automobile tire is 1.88 atm at 25.0 degrees Celsius. What
will be the pressure if the temperature warms up to 37.0 degrees Celsius?
Assume the volume and the amount of the gas are constant. *
a. 1.81 atm
b. 2.78 atm
c. 1.96 atm
d. 1.27 atm

Answers

Answer:

Option "C" is the correct answer to the following question.

Explanation:

Given:

Pressure in an automobile tire (P) = 1.88 atm

Temperature (K) = 25°C = 273 + 25 = 298 Kelvin

New temperature (K1) = 37°C = 273 + 37 = 310 Kelvin

Find:

New pressure in an automobile tire (P1) = ?

Computation:

[tex]\frac{P}{K}= \frac{P1}{K1} \\\\\frac{1.88}{298}= \frac{P1}{310}\\\\1.9557[/tex]

New pressure in an automobile tire (P1) = 1.9557

New pressure in an automobile tire (P1) = 1.96 (Approx)

what is the total number of moles of solute in 2230 ml of 3.0 M NaOH solution.

Answers

The total number of moles of solute in 2230 mL of a 3.0 M NaOH solution is calculated by converting the volume to liters and multiplying by the molarity, resulting in 6.69 moles of NaOH.

The total number of moles of solute in 2230 mL of 3.0 M NaOH solution can be calculated by using the definition of molarity, which is the number of moles of solute per liter of solution. The following steps are used for the calculation:

Convert the volume from milliliters (mL) to liters (L), knowing that 1 L = 1000 mL.Multiply the volume in liters by the molarity (M) to find the total moles of solute.

First, convert 2230 mL to liters: 2230 mL
1000 mL/L = 2.23 L.

Next, multiply the volume by the molarity: 2.23 L × 3.0 M = 6.69 moles of NaOH.

Therefore, the correct answer is that there are 6.69 moles of NaOH in 2230 mL of a 3.0 M NaOH solution.

Science Question:
Why does the same side of the moon always face Earth?


The rotational period of the moon is different than one revolution around Earth.


The rotational period of the moon is equal to one revolution around Earth.


The rotational period of Earth is the same as that of the moon.


The rotational period of Earth is equal to one revolution around Earth.

Answers

Answer:

The rotational period of the moon is equal to one revolution around Earth.

I think  this is the answer am not that positive.

Explanation

Only one side of the Moon is visible from Earth because the Moon rotates on its axis at the same rate that the Moon orbits the Earth – a situation known as synchronous rotation, or tidal locking. The Moon is directly illuminated by the Sun, and the cyclically varying viewing conditions cause the lunar phases.

Answer:

The rotational period of the moon is equal to one revolution around the earth

Explanation:

I took the test. Hopes this helps :)

What type of energy does a rock resting on top of the hill have?
A. Electoral energy
B. Kinetic energy
C. Potential energy
D. Radiant energy

Answers

C is the answer to the problem
The answer is C potential energy, hope this helps :)

The weight of the atmosphere is called what?
A. Wind
B. Gravity
C. Air pressure
D. Temperature

Answers

Answer:

The correct answer is C. Air pressure. :)

Explanation:

Air preasure is the amount of gravitational force acting against an object.

Jill is studying the temperature output of an ammonium chloride hand warmer. What apparatus will best help her monitor the
temperature change of the reaction?
calorimeter
colorimeter
hydrometer
thermometer​

Answers

Answer:

Thermometer

Explanation:

Because a thermometer helps to measure temperatures

Answer:

calorimeter

Explanation:

hope this helps :)

disease causing bacteria need oxygen to survive.
true or false

Answers

Answer:

true

Explanation:

its a guess

Disease causing bacteria need oxygen to survive is true.

What are diseases?

Diseases are defined as a specific aberrant condition that adversely affects an organism's structure or function on the whole or in part but is not immediately caused by an external harm. The onset of chronic diseases may be delayed by eating healthfully, exercising regularly, and abstaining from cigarettes and excessive alcohol use, among other factors.

Bacteria are defined as the creatures without a proper nucleus and only a few organelles that are prokaryotic unicellular organisms. The bacteria in our bodies help our bodies digest food, help us access nutrients, and neutralize poisons. Three distinguishing characteristics of bacteria are: 1) their lack of membrane-bound organelles, 2) their unicellularity, and 3) their small size.

Thus, disease causing bacteria need oxygen to survive is true.

To learn more about disease, refer to the link below:

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vanuation Question
1. What is the number one killer of teenagers?
O Speeding
Reckless driving
Driving under the influence
O Distracted driving​

Answers

Reckless driving I think

What advantage does gasoline have over electricity for cars?

Answers

You don’t have to stop & charge so often , you can just fill up & go

Final answer:

Gasoline has a higher energy density than electricity stored in lithium-ion batteries, enabling more energy to be carried per unit of weight. Gasoline vehicles can refuel quickly, offering convenience for long-distance travel, while electric vehicles require longer recharge times. Additionally, gasoline's safety profile is relatively high given its energy content, as it burns rather than explodes.

Explanation:

One of the main advantages that gasoline has over electricity for powering cars is its higher energy density. Gasoline contains approximately 13 kWh/kg, while the energy density of lithium-ion batteries is about 0.2 kWh/kg, which is substantially lower. This means that gasoline can deliver more energy per unit of weight than batteries can, making it a more energy-dense fuel source.

An additional advantage is the rapid refueling capability of gasoline vehicles. A car can fill its tank with gasoline at a rate of 15 MW, allowing it to be ready for further travel in a matter of minutes, whereas electric cars often require hours to fully recharge. This convenience factor is a significant benefit for long-distance travel or in situations where quick refueling is necessary.

Safety is another aspect where gasoline has an advantage. Although gasoline is flammable, it is not as explosive as one might think—the vapor mix with oxygen burns rather than explodes, making it relatively safe for an energy source with such high energy content.

Muscles perform what types of energy transformation?
a.) Kinetic to Potential
b.) Kinetic to Electrical
c.) Thermal to Radiant
d.) Chemical to Kinetic

Answers

Answer:

d

Explanation:

Inside of your muscles, there are fibers that are always ready to use your body's energy currency - ATP - and convert that into motion. Since they use ATP, which is a form of chemical energy, and turn it into motion, or kinetic energy, the correct answer is d. Hope this helps!

Final answer:

Option d) Muscles transform chemical energy into kinetic energy during contraction, using oxygen and food molecules to perform work and produce motion.

Explanation:

During muscle contraction, the potential energy stored in the form of chemical bonds in food molecules and oxygen is transformed into the kinetic energy of motion as the muscles do work. This can be observed through the consumption of oxygen and nutrients, the production of waste products like carbon dioxide, and the release of heat.

Moreover, the transformation of energy in muscles also results in an increased blood supply to bring nutrients and oxygen to the muscle cells efficiently and to carry away waste products.

The correct answer to the question 'Muscles perform what types of energy transformation?' is (d) Chemical to Kinetic.

How many liters of 1.20 M calcium nitrate are required to produce .1 moles of calcium sulfate? Please balance the equation before solving the problem.

Answers

Answer:

0.083L

Explanation:

We'll begin by writing the balanced equation for the reaction. This is given below:

Ca(NO3)2 + H2SO4 —> CaSO4 + 2HNO3

Next, we shall determine the number of mole of Ca(NO3)2 needed to produce 0.1 mole of CaSO4.

From the balanced equation above,

1 mole of Ca(NO3)2 reacted to produce 1 mole of CaSO4.

Therefore, 0.1 mole of Ca(NO3)2 will also react to produce 0.1 mole of CaSO4.

Finally, we can determine the volume of Ca(NO3)2 needed for the reaction as follow:

Mole of Ca(NO3)2 = 0.1 mole

Molarity of Ca(NO3)2 = 1.20M

Volume =?

Molarity = mole /Volume

Volume = mole /Molarity

Volume = 0.1/1.2

Volume = 0.083L

Therefore, 0.083L of Ca(NO3)2 is needed for the reaction.

WILL MARK BRAINLIEST FOR CORRECT ANSWER!!!!!!!!!!

The emission of what type of particle from a nucleus will not cause a transmutation?

A) positron
B) proton
C) neutron
D) alpha particle

Answers

Answer:

the answer is c

Explanation:

Answer is C- neutron

Which answer choice correctly describes the gas law and physical changes represented by the image?

a. The image shows Boyle’s law because volume increases as pressure increases.

b. The image shows Boyle’s law because volume decreases as pressure increases.

c. The image shows Charle’s law because volume decreases as pressure increases.

d. The image shows Charle’s law because as volume increases as pressure increases.

Answers

Answer:

A. The image shows Boyle's Law because volume decreases as pressure increases.

Explanation:

According to Boyle's Law, at constant temperature, pressure and volume have inverse relation that is as pressure would increase, volume would decrease.

According to Charles Law, at constant pressure, the volume is directly proportional to temperature.

According to the given graph and diagram, the temperature is constant and volume and pressure have inverse relation.

Thus, option A is correct.

A. The image shows Boyle’s law because volume increases as pressure increases

does anyone know this?

Answers

The total pressure = 1.0atm
The nitrogen is contributing 0.30atm
The oxygen is contributing 0.25atm
This means that argon must be contributing 0.45atm because 1 - (.3+.25) =0.45
You just have to know that the pressures add up to the total pressure

What mass of H₂O is formed when excess H₂ reacts with 64 g of O₂
2(H2)+(O2)---->2(H2O)
18g
36g
72g
144g

Answers

Answer: 72 g of [tex]H_2O[/tex] is formed.

Explanation:

To calculate the moles :

[tex]\text{Moles of solute}=\frac{\text{given mass}}{\text{Molar Mass}}[/tex]    

[tex]\text{Moles of} O_2=\frac{64}{32}=2moles[/tex]

[tex]2H_2+O_2(g)\rightarrow 2H_2O[/tex]

As  [tex]H_2[/tex] is the excess reagent, [tex]O_2[/tex] is the limiting reagent as it limits the formation of product.

According to stoichiometry :

1 mole of [tex]O_2[/tex] produce=  2 moles of [tex]H_2O[/tex]

Thus 2 moles of [tex]O_2[/tex] will require=[tex]\frac{2}{1}\times 2=4moles[/tex]  of [tex]H_2O[/tex]

Mass of [tex]H_2O=moles\times {\text {Molar mass}}=4moles\times 18g/mol=72g[/tex]

Thus 72 g of [tex]H_2O[/tex] is formed.

Which compound will conduct electricity when it is dissoved in water
CHA
Cusos
Citos

Answers

Answer:

Electrolyte Solutions

An electrolyte is any salt or ionizable molecule that, when dissolved in solution, will give that solution the ability to conduct electricity. This is because when a salt dissolves, its dissociated ions can move freely in solution, allowing a charge to flow.

Explanation:

Answer:

C. CuSO4

Explanation:

Trust

Carlos stomps a soda con flat and throw it away. Which of the following statements BEST describes the change made in the soda can?
The soda can kept the same mass as it changed in shape only
The soda can lost mass as it was changed into a smaller size
The soda con gained more moss because its shape changed
The soda can lost mass as it was crumpled and changed form

Answers

Answer:

The soda can kept the same mass as it changed in shape only

Explanation:

Law of Conservation states "mass cannot be created or destroyed" therefore this is why the mass hasn't changed, but when it was smashed the shape changed.

Final answer:

The soda can's mass remains the same after being stomped and flattened, as no matter is added or removed during this physical change, which is explained by the Law of Conservation of Mass.

Explanation:

The statement that best describes the change made in the soda can after Carlos stomps on it is that the soda can kept the same mass as it changed in shape only. This is explained by the Law of Conservation of Mass, which states that the mass of a closed system of substances will remain constant, regardless of the processes acting inside the system. Therefore, even though Carlos changed the can's shape by stomping on it, he did not add or remove matter from the can, so its mass remained unchanged. This principle is crucial in chemistry and holds true for both physical changes, like changing the shape of a can, and chemical changes, where substances may change form but the total mass remains constant.


Andrew noticed that the plastic in his chair seat didn't feel as cold as the metal legs. What statement best explains this observation?

A) Plastic is an insulator, so it stores warmth in the room.
B) The metal absorbs cold air in the room at a faster rate than plastic.
C) Metal is a conductor of heat so it transmits warmth away from Andrew's hand at a faster rate than plastic.
D) Metal is a conductor of heat, so it transmits its heat to the plastic until the plastic reaches room temperature.

Answers

Answer:

Metal is a conductor of heat so it transmits warmth away from Andrew's hand at a faster rate than plastic.

Explanation:

remember, cold air never existed. only the lack of heat :)

Why is water from an aquifer more likely to be cleaner than water from other sources?
Select one:
because it rises to the surface near the ocean
because pollutants are filtered by rock and soil deep within Earth
because it receives water directly from precipitation
because it forms where fresh and salt water meet

Answers

Answer:

last one

Explanation:

Answer:

2nd one

Explanation:

Sand dunes protect beaches against erosion and flooding due to storms.
Which human activity would have the most negative impact on dune grasses and the coast?
driving vehicles along the beach
building houses near the beach
walking on the dunes of the beach
allowing kids to play on the beach

Answers

Answer:

B. Building houses near the beach

Explanation:

it was right on edge

Sand dunes protect beaches against erosion and flooding due to storms. Building houses near the beach human activity would have the most negative impact on dune grasses and the coast. Therefore, option B is correct.

What is erosion ?

The process of removing soil, rock, or dissolved material from one area on the Earth's crust and moving it to another, where it is deposited, is known as erosion. Erosion differs from weathering, which is a static process.

When dirt is exposed to high winds, heavy rains, and moving water, soil erosion primarily takes place. Some human activities, particularly farming and clearing land, make soil more prone to erosion.

Beyond the loss of agricultural land, soil erosion has other negative repercussions. In streams and rivers, it has increased pollution and sedimentation, blocking these waterways and resulting in a loss in fish and other species. Additionally, deteriorated soils are frequently less able to retain water, which can make floods worse.

Thus, option B is correct.

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Is the following equation balanced? SO3 + 2H2O H2SO4 no yes

Answers

Answer: No

Explanation: It's not balanced because four oxygen atoms in H2SO4,  whereas there are 5 oxygen atoms in the reactants side. Also, there's more hydrogen atoms on the reactants side.

I hope this helps!

Answer:no

Explanation:

It's not balanced because four oxygen atoms in H2SO4

Choose the correct energy transformation for the burning of a piece of wood. A. heat energy to light energy B. light energy to heat energy C. chemical potential energy to heat energy D. heat energy to chemical potential energy

Answers

Answer:

C

Explanation:

In the case of burning wood, stored potential energy in the wood is released due to heating by other excited atoms.

Final answer:

The burning of wood transforms chemical potential energy stored in the wood into heat energy, making option C the correct answer.

Explanation:

The correct energy transformation for the burning of a piece of wood is chemical potential energy to heat energy. This process is an example of a chemical reaction where the chemical energy stored in wood's molecules is released as heat and light energy when the wood combusts.

The chemical potential energy stored in the bonds of the wood is released as heat and light during the combustion process. This chemical potential energy is converted into heat energy, which is evident through the warmth generated by the burning wood. Additionally, some of this energy may also be transformed into light, but the primary conversion is from chemical potential energy to heat.

round 23,455 into 4 significant figures: ______ cm 23.46
23.40
23.45

Answers

Answer:

23.46

Explanation:

Please need asap. 50 points ​

Answers

Is that the only paper?

Answer:

just do the lab or what ever

Explanation:

because your just taking notes and taking data

For an Ohmic conductor, tripling the voltage without changing the resistance will cause the current to
A.
increase by a factor of 9.
B.
decrease by a factor of 9.
C.
increase by a factor of 3.
D.
decrease by a factor of 3.

Answers

Answer:

a

Explanation:

A 100g sample of Carbon-14 has a half-life of 5 years. How much Carbon-14 is left after 10 years?

Answers

Answer: The amount of carbon-14 left after 10 years is 25 g

Explanation:

Formula used :

[tex]a=\frac{a_o}{2^n}[/tex]

where,

a = amount of reactant left after n-half lives = ?

[tex]a_o[/tex] = Initial amount of the reactant = 100 g

n = number of half lives =[tex]\frac{\text {given time}}{\text {half life}}=\frac{10}{5}=2[/tex]

Putting values in above equation, we get:

[tex]a=\frac{100g}{2^2}[/tex]

[tex]a=\frac{100g}{4}=25g[/tex]

Therefore, the amount of carbon-14 left after 10 years is 25 g


Curious Carl and his lab partner added small pieces of various metals to HCl. Magnesium (Mg) and zinc (Zn) reacted vigorously with HCl, releasing hydrogen gas. This equation represents the reaction of zinc in hydrochloric acid.

Zn + 2HCl → ZnCl2 + H2
What is the half reaction for the reduction of hydrogen in the reaction?

A) 2HCl → + 2e- + H2(g)
B) H + Cl → + 2e- + H2(g)
C) 2H+ + 2e- → H2(g)
D) 2H+ - 2e- → H2(g)

Answers

Answer:

I just took it on use test prep. the answer is C. 2H + 2e → H2(g)

Answer:B

Explanation:USA test prep

How many moles of gas are contained in 890.0 mL at 21.0 °C and 750.0 mm Hg pressure?

Answers

Answer:

(0.9868 atm)(0.89 L) = (x)(0.0821 L-atm)(294 K)

0.87825 = (x) 24.1374

x = 0.03638 moles :)

Explanation:

Given the value of the temperature and the pressure, the amount of the ideal gas contained in the given volume is 0.036mol.

Ideal Gas Law

The Ideal gas law or general gas equation emphasizes on the state or behavior of a hypothetical ideal gas. It states that "the pressure multiplied by volume is equal to moles multiply by the universal gas constant multiply by temperature.

It is expressed as;

PV = nRT

Where P is pressure, V is volume, n is the amount of substance, T is temperature and R is the ideal gas constant ( 0.08206 Latm/molK )

Given the data in the question;

Volume of gas V = 890.0 mL = 0.89LTemperature T = 21.0°C = 294.15KPressure P = 750.0mmHg = 0.986842atmAmount of gas n = ?

To determine the amount of  gas, we substitute our values into the expression above.

PV = nRT

n = PV / RT

n = ( 0.986842atm × 0.89L ) / ( 0.08206 Latm/molK × 294.15K )

n = 0.87828938Latm / 24.137949Latm/mol

n = 0.036mol

Therefore, given the value of the temperature and the pressure, the amount of the ideal gas contained in the given volume is 0.036mol.

Learn more about Ideal Gas Law here: brainly.com/question/4147359

13. What instrument is used routinely to check a person's exposure to radiation?
Geiger counter
scintillation counter
film badge
moderating rod

Answers

The answer is Film badge
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