calculate the molar mass of iron oxide

Answer:

C3H8 + 5O2 ‐‐‐‐‐‐‐‐> 4H2O + 3CO2

Answer:

All ions must a overall charge

Explanation:

Answer:

i belive its B

Explanation:

Answer: a supposition or proposed explanation made on the basis of limited evidence as a starting point for further investigation.

Explanation: definition

Answer: The empirical formula of X  is [tex]Cr_2O_3[/tex]

Explanation:

If percentage are given then we are taking total mass is 100 grams.

So, the mass of each element is equal to the percentage given.

Mass of Cr = 68.4 g

Mass of O = 31.5 g

Step 1 : convert given masses into moles.

Moles of Cr =[tex]\frac{\text{ given mass of Cr}}{\text{ molar mass of Cr}}= \frac{68.4g}{52g/mole}=1.31moles[/tex]

Moles of O =[tex]\frac{\text{ given mass of O}}{\text{ molar mass of O}}= \frac{31.5g}{16g/mole}=1.97moles[/tex]

Step 2 : For the mole ratio, divide each value of moles by the smallest number of moles calculated.

For Cr = [tex]\frac{1.31}{1.31}=1[/tex]

For O = [tex]\frac{1.97}{1.31}=1.5[/tex]

The simple whole number ratio of Cr : O= 2: 3

Hence the empirical formula is [tex]Cr_2O_3[/tex]

Mole measure the number of elementary entities of a given substance that are present in a given sample. Therefore, 9.033×10²³ is the number of molecules in 1.500 mole of H[tex]_2[/tex]O.

The SI unit of amount of substance in chemistry is mole. The mole is used to measure the quantity or amount of substance. We know one mole of any element contains 6.022×10²³ atoms which is also called Avogadro number.

Mathematically,

number of atoms/molecules=number of moles × 6.022×10²³(Avogadro number)

number of moles =1.500 mole

substituting all the given values in the above equation, we get

number of atoms/molecules=1.500  × 6.022×10²³(Avogadro number)

number of atoms/molecules =9.033×10²³molecules

Therefore, 9.033×10²³ is the number of molecules in 1.500 mole of H[tex]_2[/tex]O.

To know more about mole, here:

https://brainly.com/question/15209553

#SPJ2

Answer:

im pretty sure its the last one

Explanation:

if plants dont have sun light they will die because the sunlight gives them the nutrients to survive

Answer:

[tex]h=12.9cm[/tex]

Explanation:

Hello!

In this case, since we can consider the beaker until the 100-mL mark as a cylinder, we can use the following equation to relate its diameter, vertical distance or height and volume:

[tex]V=\pi h\frac{d^2}{4}[/tex]

Thus, since we know the diameter, volume (which is equivalent to 600 cm³) and π, we can plug in to obtain:

[tex]600cm^3=\pi *h*\frac{(77.0mm)^2}{4}[/tex]

It means it is necessary to take the mm to cm and solve for h:

[tex]h=\frac{600cm^3}{\pi*\frac{(7.70cm)^2}{4}} \\\\h=12.9cm[/tex]

Best regards!

The distance between each 100 mL mark is 2.15 cm.

The volume of a cylinder is obtained using the formula;

V = πr^2h

Now, we have the following information;

Volume of the cylinder = 600. mL or 600 cm^3

Diameter of the cylinder = 77 mm or 7.7 cm

Radius of the cylinder = 7.7/2 = 3.85 cm

Height of the cylinder  = h

Hence;

600 = 3.142 × ( 3.85 )^2 × h

h = 600/3.142 × ( 3.85 )^2

h = 12.88 cm

There are six 100 mL marks on the beaker, the distance between each 100 mL mark =  12.88 cm/6 = 2.15 cm

Learn more about volume: https://brainly.com/question/12748872

Answer:

the effects that the scientists are causing by manipulating varuables

Answer:

1.204428 * 10^24 atoms

Explanation:

Number of moles = 2 mol

Number of atoms = ?

The relationship between moles and atoms is given by the avogadro's umber. This is the number of units in one mole of a substance.  The units can be atoms, ions etc In this case it is atoms. The number is equal to  6.02214076 * 10^23

This means;

1 mol = 6.02214076 * 10^23

2 mol = x

Upon solving for x,

x = 2 * 6.02214076 * 10^23

x = 12.04428 * 10^23

x = 1.204428 * 10^24 atoms

Answer:

mass of HNO₃ = 0.378 g

Explanation:

Normality = Molarity * number of equivalents

Molarity = Normality/number of equivalents

normality of HNO₃ = 0.30 N, Volume = 20 mL

HNO₃ ionizes in the following way:

HNO₃(aq) ----> H⁺ + NO₃⁻

Therefore, number of equivalents for HNO₃ is 1

molarity of HNO₃ = 0.30/1 =0.30 mol/dm³

Using the formula, molarity = number of moles/volume in liters

number of moles = molarity * volume

Number of moles of HNO₃ = 0.30 mol/dm³ * 20ml * 1 dm³ /1000 mL

number of moles = 0.006 moles

From the formula, mass = number of moles * molar mass

molar mass of HNO₃ = 63.0 g/mol

mass = 0.006 * 63

mass of HNO₃ = 0.378 g

Answer:

D

Explanation:

Answer:

C they have different frames of reference

Explanation:

Answer:

Sweets are sold loose, or pre-packed in 120g bags.

The 120 g bags are £1.49 each.

The loose sweets are £0.89 for 100g.

By calculating the price per gram, determine which is better value. Show your working.

Answer:

I think you should use distillation cauze it helps to separate two mixtures

Answer:

A.) distillation

Explanation:

edge 2021

The question is incomplete, the complete question is;

The compound magnesium nitrate is a strong electrolyte. Write the reaction when magnesium nitrate is put into water:

Answer:

Mg(NO3)2(s)--------->Mg^2+(aq) + 2NO3^-(aq)

Explanation:

When we say that a compound is a strong electrolyte, we mean that that the compound dissociates completely in solution to form its ions.

This means that all strong electrolytes attain 100% dissociation of the solid in water according to its stoichiometric equation.

For magnesium nitrate, the reaction equation is;

Mg(NO3)2(s)--------->Mg^2+(aq) + 2NO3^-(aq)

Answer: A chemical symbol is a one- or two-letter designation of an element. Compounds are combinations of two or more elements. A chemical formula is an expression that shows the elements in a compound and the relative proportions of those elements.

Answer:

erosion.

Explanation:

Answer:

Reflection

Explanation:

The light from Earth's surface, reflected back towards the Moon, can illuminate it all the same. This is why, when the Moon is in a crescent phase, you can still see features on the dark portion of the Moon: we call this reflected, illuminating light the phenomenon of Earthshine.

Answer:

plants

Explanation:

because it produces ( i am a third grade student and don't know if it is right or not)

0.042 moles of Hydrogen evolved

Given

I = 1.5 A

t = 1.5 hr = 5400 s

Required

Number of Hydrogen evolved

Solution

Electrolysis of water ⇒ decomposition reaction of water into Oxygen and Hydrogen gas.

Cathode(reduction-negative pole) : 2H₂O(l)+2e⁻ ⇒ H₂(g)+2OH⁻(aq)

Anode(oxidation-positive pole) : 2H₂O(l)⇒O₂(g)+4H⁻(aq)+4e⁻

Total reaction : 2H₂O(l)⇒2H₂(g)+O₂(g)

So at the cathode H₂ gas is produced

Faraday : 1 mole of electrons (e⁻) contains a charge of 96,500 C

[tex]\tt mol~e^-=\dfrac{Q}{96500}[/tex]

Q = i.t

Q = 1.5 x 5400

Q = 8100 C

mol e⁻ = 8100 : 96500 = 0.084

From equation at cathode , mol ratio e⁻ : H₂ = 2 : 1, so mol H₂ = 0.042

The question is incomplete, the complete reaction equation is;

The concentration of a hydrogen peroxide solution can be determined by titration

with acidified potassium manganate(VII) solution. In this reaction the hydrogen

peroxide is oxidised to oxygen gas.

A 5.00 cm3 sample of the hydrogen peroxide solution was added to a volumetric flask

and made up to 250 cm3 of aqueous solution. A 25.0 cm3 sample of this diluted

solution was acidified and reacted completely with 24.35 cm3 of 0.0187 mol dm–3

potassium manganate(VII) solution.

Write an equation for the reaction between acidified potassium manganate(VII)

solution and hydrogen peroxide.

Use this equation and the results given to calculate a value for the concentration,

in mol dm–3, of the original hydrogen peroxide solution.

(If you have been unable to write an equation for this reaction you may assume that

3 mol of KMnO4 react with 7 mol of H2O2. This is not the correct reacting ratio.)

Answer:

2.275 M

Explanation:

The equation of the reaction is;

2 MnO4^-(aq) + 16 H^+(aq) + 5H2O2(aq) -------> 2Mn^+(aq) + 10H^+ (aq) + 8H2O(l)

Let;

CA= concentration of MnO4^- =  0.0187 mol dm–3

CB = concentration of H2O2 = ?

VA = volume of MnO4^- = 24.35 cm3

VB = volume of H2O2 = 25.0 cm3

NA = number of moles of  MnO4^- = 2

NB = number of moles of H2O2 = 5

From;

CAVA/CBVB = NA/NB

CAVANB = CBVBNA

CB = CAVANB/VBNA

CB = 0.0187 * 24.35 * 5/25.0 * 2

CB = 0.0455 M

Since  

C1V1 = C2V2

C1 = initial concentration of H2O2 solution = ?

V1 = initial volume of H2O2 solution =  5.0 cm3

C2 = final concentration of H2O2 solution= 0.0455 M

V2 = final volume of H2O2 solution = 250 cm3

C1 = C2V2/V1

C1 = 0.0455 * 250/5

C1 = 2.275 M

Answer:

Not affected.

Explanation:

Kinetic energy of the dominoes not affected if the first domino did not hit the second one because no kinetic energy is lost due to no collision. If the first domino hit the second one, its kinetic energy decreases and changes in other form of energy such as heat and sound energy etc. But when there is no collision occur, then there is no change in the kinetic energy of dominoes.

If a cell is placed in an isotonic solution, there will be no net flow of water into or out of the cell, and the cell's volume will remain stable. If the solute concentration outside the cell is the same as inside the cell, and the solutes cannot cross the membrane, then that solution is isotonic to the cell.

Answer:

D. liquid

Explanation:

Matter, which is any substance that has weight and occupies space, can exists in three states namely: solid, liquid and gaseous. In this question, water is being described as matter.

According to this question, a sample of water of volume 2litres is shaped like a cylinder in one container and shaped like a rectangle in another larger container. Based on this observation, the water sample is in a LIQUID STATE because a liquid has no indefinite shape but takes the shape of its container.

Hence, this water sample, takes the shape of its cylindrical container in the first scenario and shape of its rectangular container in the second scenario.

Answer:

120.37 g/mol is the molar mass of magnesium sulfate

Answer:

1.807×10and at the top of ten put -24

Answer:

create a plan

the ways of of a student to set a goal

1. Write clear and measurable goals

2.Create a specific plan for each goal

3.Read your goals daily and visualize yourself accomplishing them

4. Reflect yourself to see if you are on target

5. Revise your action plans if needed.

1.)make a plan

2.)make a schedule

5.)pace him or herself

Answer:

a. 0.528 M .

Explanation:

Hello!

In this case, since the given by-mass percent can be written as:

[tex]\frac{10gCdSO_4}{100g\ sol}[/tex]

By using the density and molar mass of the solute, cadmium sulfate, we can compute the molarity, by also making sure we convert from mL to L of solution:

[tex]M=\frac{10gCdSO_4}{100g\ sol}*\frac{1molCdSO_4}{208.46gCdSO_4} *\frac{1.10g\ sol}{1mL\ sol}*\frac{1000mL}{1L} \\\\ M=0.528M[/tex]

Thereby, the answer is a. 0.528 M .

Best regards.

The molarity of the solution of 10% by mass cadmium sulfate [tex](CdSO_4)[/tex] is approximately 0.479 M. The correct option is C.

To calculate molarity we need to find out how many moles of CdSO4 are present in the solution.

Given:

We need to calculate the mass of [tex]CdSO_4[/tex]:

Mass of [tex]CdSO_4[/tex] = (10% / 100%) * Total mass of the solution

Mass of [tex]CdSO_4[/tex] = (10 / 100) * 1000 g (since the volume is 1 L, and the density is 1.10 g/mL)

Mass of [tex]CdSO_4[/tex] =  100 g

So, the number of moles of CdSO4:

Number of moles of [tex]CdSO_4[/tex] = Mass of CdSO4 / Molar mass of CdSO4

Number of moles of [tex]CdSO_4[/tex] = 100 g / 208.46 g/mol

Number of moles of [tex]CdSO_4[/tex] ≈ 0.479 moles

Then, we calculate the molarity of the solution:

Molarity = Number of moles of CdSO4 / Volume of the solution (in liters)

Molarity = 0.479 moles / 1 L

Molarity ≈ 0.479 M

Hence, the molarity of the solution of 10% by mass cadmium sulfate [tex](CdSO_4)[/tex] is approximately 0.479 M. The correct option is C.

Learn more about Molarity, here:

https://brainly.com/question/31545539

#SPJ6

Answer:

When you heat up water, the water molecules start moving around faster and faster. ... So hot water is less dense than cold water. When you put the two together with the hot water on the bottom, the hot water rises to the top, mixing with the cold water along the way and creating purple water.

Explanation:

have a great day :)

Why can gases and liquids be paired but not solids?

The atoms and molecules in gases are much more spread out than in solids or liquids. They vibrate and move freely at high speeds. A gas will fill any container, but if the container is not sealed, the gas will escape. Gas can be compressed much more easily than a liquid or solid.

Answer:

Energy produced deep inside Earth heats rock in the mantle. ... As it becomes less dense, the heated rock rises toward Earth's surface. The cooler, denser rock surrounding the heated rock sinks, as Figure 5 shows. In this way, heat inside Earth moves toward the cooler crust.

Explanation:

do you like my og name

Energy from Earth’s interior affect surface changes due to:

Learn more:

brainly.com/question/25543134