Se someten a combustion 0,452g de un compuesto de C,H y N de masa molecular 80. Al recoger el CO2 y el H2O producidas obtenemos 0,994 g y 0,203 respectivamente. Determine formula empirica y formula molecular

Answers

Answer 1

Answer:

Fórmula empírica: C₂H₂N

Fórmula molecular: C₄H₄N₂

Explanation:

Un compuesto que contiene carbono hidrógeno y nitrógeno con fórmula CₐHₓNₙ es sometido a combustion produciendo:

CₐHₓNₙ + O₂ → aCO₂ + x/2 H₂O + nNO₂

Con la masa de dióxido de carbono y agua podemos encontrar las moles de carbono e hidrógeno y su aporte a los 0.452g de muestra que fueron puestos en combustión, así:

Moles C:

Moles C = Moles CO₂ = 0.994g CO₂ ₓ (1mol / 44g) = 0.0226 moles C

Masa C: 0.0226 moles C ₓ (12.01g / mol) = 0.271g Carbono hay en la muestra

Moles H:

Moles H = 2 Moles H₂O = 0.203g H₂O ₓ (1mol / 18g) = 0.0113 moles H₂O = 0.0226 moles H

Masa H: 0.0226 moles H ₓ (1.01g / mol) = 0.023g Hidrógeno hay en la muestra

Así, la masa de nitrógeno en la muestra y sus moles son:

Masa N = 0.452g - 0.271g C - 0.023g H

Masa N = 0.158g Nitrógeno

Y su moles son:

0.158g ₓ (1 mol / 14.01g) = 0.0113 moles N

Con las moles de C, H y N podemos determinar la formula empírica que se define como: "La relación de números enteros más simple entre la cantidad de átomos presentes en una mólecula. Si usamos como base las moles de nitrógeno (Valor menor):

Relación H/N: 0.0226 mol / 0.0113 mol = 2

Relación C/N: 0.0226 mol / 0.0113 mol = 2

Relación N/N: 0.0113 mol / 0.0113 mol = 1

Así, la fórmula empírica es:

C₂H₂N

Esta fórmula empírica tiene una masa molar de:

2C = 2*12 g/mol = 24g/mol

2H = 2*1g/mol = 2g/mol

N = 14g/mol

24+14+2 = 40g/mol

Como la masa molecular del compuesto es 80g/mol (Dos veces la de la fórmula empírica, la fórmula molecular es 2 veces la fórmula empírica:

C₄H₄N₂

Related Questions

Select the correct answer from each drop-down menu. At chemical equilibrium, the amount of because .

Answers

Answer:

The answer that completes the question are in BOLD:

At chemical equilibrium, the amount of PRODUCT AND REACTANT REMAIN CONSTANT because the RATES OF THE FORWARD AND REVERSE REACTIONS ARE EQUAL.

Explanation:

In a reversible chemical reaction, an equilibrium is said to be achieved when the rates of the forward reaction is equal to that of the reverse reaction. A reversible reaction is one in which products are formed from reactants simultaneously with the formation of reactants from products.

The combination of two or more substances called REACTANTS gives rise to another substance called PRODUCT, which can in turn give rise to Reactants again. With time, the rate at which the reactants give rise the products, which is called the FORWARD REACTION will be equal to the rate at which the products give rise to the reactants, which is called REVERSE REACTION. At this point, the chemical reaction is said to be in a STATE OF EQUILIBRIUM.

When the rate at which both reaction occurs becomes equal i.e. at an equilibrium state, the concentration of both the reactants and the products becomes constant i.e. no longer changes. Hence, the amount of the reactants forming the products is the same as the amount of products forming the reactants.

N.B: At chemical equilibrium, the amount of the reactants and products does not necessarily equals zero (0). It simply means that there is no net change in the concentration/amount of both reactants and products.

How many moles are present in 136 grams of MgCl2? 1.46 mol 1.43 mol 2.27 mol

Answers

Answer:

1.43 mol

Explanation:

which of the following molecules would you expect to be optically active

1. CCl2F2
2. 2-methyl butane
3. butan-2-ol​

Answers

Answer:

waaaaaaaaaaqwwwwwwwwwwww

What are the properties of alkynes

Answers

These double-bonded compounds are colourless and odourless in nature. ...
Solubility. The alkenes are insoluble in water due to their nonpolar characteristics. ...
Boiling Point. The boiling points of the compounds increase as the number of carbon atoms in the compound increases. ...
Melting Point. ...
Polarity.
Alkynes are nonpolar, unsaturated hydrocarbons with physical properties similar to alkanes and alkenes. Alkynes dissolve in organic solvents, have slight solubility in polar solvents, and are insoluble in water. Compared to alkanes and alkenes, alkynes have slightly higher boiling points.

Alkenes are chemically more reactive than alkanes.
This because alkenes are unsaturated hydrocarbons that have a double bond, C=C, between two carbon atom.
Almost all of the chemical reactions of alkene occur at the double bond.

Match the set of measurements of the boiling point of water with the best

description.

Measurements

Description

6. 103 °C, 90 °C, 101 °C

a.

Precise

7. 100 °C, 99 °C, 100 °C

b.

Accurate

8. 105 °C, 106 °C, 105 °C

c. Both accurate and precise

9. 99 °C, 101 °C, 100 °C

d. Neither accurate nor precise

Answers

Answer:

Matching

6.D

7.A

8.C

9.B

Explanation:

Took test

103 °C, 90 °C, 101 °C Neither accurate nor precise, 100 °C, 99 °C, 100 °C are Precise, 105 °C, 106 °C, 105 °C are Both accurate and precise, 99 °C, 101 °C, 100 °C are Accurate. These are the correct set of measurements of the boiling point of water.

what are  boiling point and melting point ?

The melting point is defined as the temperature at which solid and liquid phases are at equilibrium state, whereas the boiling point is defined as the temperature at which the pressure of a vapor of a  liquid is equal to the external pressure.

Melting point in which the melting of solid occur to become a liquid at a given temperature, here the molecules gain enough amount of kinetic energy to get the intermolecular forces to convert into another form.

In case of Boiling point the liquid phase enters into the gaseous phase, when the external pressure is high than a temperature for the vapor pressure equal to the external pressure.

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0.024 is how many significant figures?

Answers

Answer:

24×10^-3

Explanation:

[tex]Move \: the\:decimal \:point\:,\\3 \:times\:to\:the \:right = 24\\\\When \:the\:decimal\:point \: moves\\\:to\:the \:right\:it\:becomes\:a \:negative\:power\\\\0.024= 24 \times 10^-^3[/tex]

PLEASE HELP WILL GIVE BRAINLIEST!!!!
If the concentration of substance A of a reversible reaction in dynamic equilibrium increases, how will the equilibrium change?
A. It will shift to create more of substance A.
B. It will shift towards the reactants.
C. It will shift towards the products.
D. It will shift to create less of substance A.

Answers

Answer:

[tex]\boxed{It\ will\ shift\ to\ create\ less\ of\ substance\ A}[/tex]

Explanation:

If the concentration of any substance A in a dynamic equilibrium increases, The equilibrium will be  shifted to its opposite side so that Substance A can be created less and the substance opposite to A can be created more so that a "dynamic equilibrium" can again be established.

does the tendency to gain electrons decrease as we go down grp 17?

Answers

Explanation:

Hi, there!!!!

Let me simply clear you..

Yes,The tendency to gain electrons (in nonmetal) decreases when we go down group 17.

The reason for above answer is when we go downwards in periodic table then the atomic size increases with the addition of number of shells and force of attraction between the nucleus and valance shell decreases. The force of attraction between the nucleus and valance shell becomes weaker due to which the force of attracting the electrons gets decreased.

So, we can say that the tendency to gain electrons decreases as we go down in periodic table.

Hope it helps....

What is the equilibrium constant of aA+bB cC +dD?

Answers

Explanation:

{c}^C . {d}^D / {a}^A . {b}^B

A baseball has a mass of 135 grams and a softball has a mass of 270 grams. In which of the following situations would they have the same momentum? The baseball and softball are thrown at the same speed in the same direction.

Answers

Answer:

The baseball is thrown twice as fast as the softball in the same direction.

Explanation:

A sample of copper is heated to 100°C and placed into a calorimeter containing 50 g of water at 25°C after a few minutes the final temperature of the system reaches 40°C how much heat in joules was released by the copper Sample

Answers

Answer:

Heat = 3138J

Explanation:

In the system, the sample of Copper is releasing heat that produce the increasing in the temperature of water.

Using the equation of calorimeter, we can find the heat released for the sample of copper (The same that is absorbed for the water):

Q = C×m×ΔT

Where Q is heat, C is specific heat (For water: 4.184J/molK), m is the mass of water (50g) and ΔT is change in temperature of water (40°C-25°C = 15°C)

Replacing:

Q = 4.184J/molK×50g×15°C

Q = 3138J is the heat released for the sample of Copper (The same absorbed for the water).

Answer:

heat=3138j

Explanation:

In the system, the sample of Copper is releasing heat that produce the increasing in the temperature of water.

Using the equation of calorimeter, we can find the heat released for the sample of copper (The same that is absorbed for the water):

Q = C×m×ΔT

Where Q is heat, C is specific heat (For water: 4.184J/molK), m is the mass of water (50g) and ΔT is change in temperature of water (40°C-25°C = 15°C)

Replacing:

Q = 4.184J/molK×50g×15°C

Q = 3138J is the heat released for the sample of Copper (The same absorbed for the water).

If two solutions with concentrations of 0.4 M sugar and 0.7 M sugar respectively are separated by a semipermeable membrane, during osmosis there is a net flow of Group of answer choices sugar molecules from the dilute to the concentrated solution sugar molecules from the concentrated to the dilute solution water molecules from the concentrated to the dilute solution water molecules from the dilute to the concentrated solution

Answers

Answer: Water molecules from the dilute to the concentrated solution

Explanation:

During Osmosis if a solution is separerated by a semipermeable membrane, the solvent (typically water) from the less concentrated solution in terms of solute goes through the semipermeable membrane to the solution with the higher concentration so that the concentrations between the solutions can be balanced.

With the above solutions therefore, water molecules would move from the solution of 0.4M of sugar to the solution with a 0.7M of sugar through the semipermeable membrane.

During osmosis, water molecules move from the dilute to the concentrated solution.

OSMOSIS:

Osmosis is the movement of water molecules from a region of higher concentration (low concentration of solute) to a region of lower concentration (higher concentration of solute).

The principle of movement is based on the concentration gradient i.e. difference in concentration across a semipermeable membrane.

According to this question, two solutions have sugar concentrations of 0.4 M sugar and 0.7 M respectively and are separated by a semipermeable membrane.

Therefore, water molecules will move from the dilute (0.4M) to the concentrated (0.7M) solution during osmosis.

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Which of the following elements has a complete outer shell of electrons? A. Iron (Fe) B. Hydrogen (H) C. Neon (Ne) D. Nitrogen (N)

Answers

Answer:

The answer is Neon

Answer:

neon

Explanation:

neon has a complete outer 2n shell

Tips for memorizing the first 20 elements of the periodic table?​

Answers

Answer:

hydrant flying with balloon, balloon has lithp letting air out, bee: really yum balloon

    =                           =                                 =                                   =

hydrogen              helium                     lithium                     beryllium

be bore on the balloon, balloon pops, hydrant drops and makes a car bomb

           =                                                                                                  =

    boron                                                                                              carbon

night row general gets hurt by car bomb nearby, that general gets off boat

        =                                

nitrogen

wearing oxygen mask, mask is full of fluride gel, then he got neon teeth

             =                                               =                                      =

         oxygen                                fluorine                                neon

(try making a story out of the elements, use your imagenation)

I will give u tips to learn whole periodic table

1. Break down the table into sections

2. Spread out the memorisation process

3. Learn the elements in a song

4. Make none sense words made from element symbols

5. Use colour to learn element groups

6. Use mnemonic device to help remember the order of elements

I am sure this will be helpful for uuu

Explanation:

How can you use the scientific method in everyday life?

Answers

You can use the scientific method everyday by asking questions and doing experiments. For example, you want to know how a fire starts, so you do an experiment with it!

List the metals Mg, Cu, Au, Na and Al in the decreasing order of their reactivity with air.

Answers

Answer:

Na is most reactiveAlcuAu is less reactiveIN HERE

Answer:

Potassium  (K)

Sodium  (Na)    

Calcium  (Ca)

Magnesium (Mg)  

Aluminium  (Al)

Iron  (Fe)  

Lead  (Pb)

Copper  (Cu)  

Silver  (Ag)

Gold  (Au)

HELP!!!!!!, I need this urgently!!!
Compare the properties of producer and water gas​

Answers

Answer:

Producer gas and water gas contain carbon monoxide and hydrogen.

When might Accurate length measurement be important?​

Answers

Answer:

When you are going to measure small lengths or objects or when you are going to measure things with great accuracy.

Explanation:

What happens when two objects when they are brought closer together The mass of both objects decrease The mass of both objects increase The gravitational force between them decreases The gravitational force between them increases

Answers

Answer:

The correct option is

The gravitational force between them increases

Explanation:

According to Newton's law of universal gravitation states that the force of attraction between two bodies is directly proportional to the product of the masses of the bodies and inversely proportional to the square of the distance of their centers from each other.

The formula for universal gravitation is given as follows;

[tex]F_{1} = F_{2} =G \times \dfrac{m_{1} \times m_{2}}{r^{2}}[/tex]

Where;

F₁, and F₂ = The gravitational forces of attraction on each mass

G = The gravitational constant

m₁ = The mass of one body

m₂ = The mass of the body

r = The distance between the centers of the two bodies

Therefore, the gravitational force of attraction on each object is inversely proportional to the as the distance between the centers of the two bodies

When the distance between the centers of the two bodies decreases, the two objects are brought closer together, the gravitational force of attraction between them increases.

Answer:

Gravitational force between two objects of masses m1/m2

Explanation:

is defined by Gm1xm2/r^2, where G is a universal constant, and r is the distance between the masses. This shows you why B is wrong; it would increase. Also, A is not a good choice, as shown. In the case of B, it would increase by say, 2/1 to 4/1 by doubling ones mass. In C's case the bottom would decrease on the fraction alot (square) if they were moved closer, thus the force would be greater.

Explanation:

in other words the  answer is The gravitational force between them increases

how will you measure the length of a curved line by using a thread? ​

Answers

A curved line or surface cannot be measured by a straight scale, a measuring tape or thread must be used instead.To measure a curved line using a thread, follow the below steps:

Tie a knot at one end of the thread.
Place the thread at the beginning of the line and try to measure a small initial portion of the line which is relatively straight.
Place your thumb at the other end of the measured portion and measure next straighter portion.
Repeat the above step till the end of line is reached. Make a knot at the end of the line.
Now, straighten the thread and measure the length of the two knots on a scale.

Explain how the energy of a toy car is transformed as it slides down a ramp. Give evidence that the energy of the car remains the same at all points on the ramp. (30 points)

Answers

Answer:

As the car starts to slide down the ramp, it is kinetic energy and when it's on the top of the ramp,  it is potential energy. We can see that the energy is now being transferred through the car and ramp.

Ou Esaplain different form
of oxygen?​

Answers

Answer:

oxygen is the chemical element with the atomic number is 8 and the symbol is o its known as called oxygen.

Explanation:

Oxygen is the most third element in the universe at they standard and temperature and pressure,and oxides most elements as other compounds.

Oxygen gas is the earth atmosphere is 21%, an oxygen is the half of the earth crust in form of oxide,oxygen is liquid and solid gas.

Oxygen atoms such as proteins and acids, fats the major organic compounds, oxygen as component of the water and carbon dioxide.

Oxygen has many characteristics :- properties and molecular structure:-

this  is a pressure and temperature  with molecular formula referred as oxygen,simply describe a double bond and molecular orbits.

Physical properties:- oxygen is highly substance and must be combustible materials, oxygen may also from using a liquid nitrogen coolant, molecular oxygen is the associated with the process of air glow.

Stellar origin :- all of the remaining to half lives to the majority of are less then milliseconds.

Occurrence:- oxygen is the process part of the element in the earth crust, free oxygen is also occurs in the world bodies.

Analysis :- analysis to the structure of vegetation and the carbon cycle on a global scale.

Calcula el %m/v de alcohol en una mezcla utilizada para la desinfección de manos formada por: 15 ml de agua (densidad=1g/ml), 105 g de etanol (densidad: 0,798 g/ml) y 4,5 gramos de jabón líquido (densidad= 1,5 g/ml)

Answers

Answer:

%m/v =70%

Explanation:

El %m/v es una unidad de concentración que se define como cien veces la división entre la masa de una sustancia (En gramos) y el volumen total en el que esta sustancia se encuentra (en mL).

En el problema, debemos hallar la masa de etanol (Alcohol) y el volumen total de la solución.

Masa alcohol:

Ya te la dan en el problema: 105g

Volumen solución:

Volumen agua: 15mL

Volumen etanol: 105g × (1mL / 0.798g) = 131mL

Volumen Jabón líquido: 4.5g × (1mL / 1.5g) = 3mL

Volumen: 15mL + 131mL + 3mL

149mL

Así, el %m/v de alcohol en la solución es:

%m/v = (105g / 149mL) × 100

%m/v =70%

If an object's mass is 70 g, and its volume is 10cm cubed, what is its density?

Answers

The answer is 7,000

If an object's mass is 70 g, and its volume is 10cm cubed,  its density is 7 centimeter cube.

What is density?

The density of any solid substance is the unit of the area occupied by it in per centimeter of the cube of the volume in the given sample and calculated by dividing the mass and the volume of the compound unit will be centimeter cube.

The mass of the given object is 70 gram and the volume is given is 10 cm to find the density,

                       Density = mass of object / volume of object

substituting the value in the formula,

                 Density = 70 / 10

                 Density = 7 centimeter cube.

Therefore, the density of the given object will be 7 centimeter cube if  an object's mass is 70 g, and its volume is 10cm cubed.

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1. Which material had the highest rate of absorption? What can you conclude about the rate
of absorption in the natural world? How might this influence climate regions?

Answers

it might be porous materials

Answer:

Air had the highest rate of absorption.  Air absorbs most of the suns heat and sun rays and air can move to different areas which are warm and colder.

Explanation:

What is ionic bond and explain it​

Answers

Answer:

An ionic bond is a chemical bonding involving the attraction between oppositely charged ions

Explanation:

On the periodic table, elements from group 1 and 7 are attracted to each other and when they bond, it's called ionic bonding. This is because of their valence electrons and ions.

Answer:

Ionic bonding is a type of chemical bonding that involves the electrostatic attraction between oppositely charged ions, and is the primary interaction occurring in ionic compounds. It is one of the main types of bonding along with covalent bonding.

100 cm^3 of oxygen diffuses through a Porous in 3second how long will it take 150 cm^3 of sulphur (iv) oxide diffuse through the same pot? ( oxygen= 16 sulphur = 32)​

Answers

Answer:

3.18 seconds

Explanation:

Given the following :

Volume of oxygen (V1) = 100cm^3

Time taken (t1) = 3 seconds

Volume of Sulphur (iv) oxide (v2) = 150cm^3

From Graham's Law of diffusion:

(r1/r2) = √(m1/m2)

Where r = rate of diffusion

m = molar mass

Note rate (r) = (volume / time)

[(V1/t1) ÷ (v2/t2)] = √(m1/m2)

(v1/t1) * (t2/v2) = √(m1/m2)

m1 = 02 = (16 * 2) = 32

m2 = SO2 = (32 + (16 * 2)) = 64

(100/3) * (t2/150) = √(32/64)

100t2 / 450 = √(32/64)

100t2 / 450 = √32 / 8

100t2 / 450 = √32 / 8

100t2 * 8 = 450 * √32

800t2 = 2545.5844

t2 = 2545.5844 / 800

t2 = 3.1819805

t2 = 3.18 seconds

It will take 3.18s for 150cm^3 of Sulphur (iv) oxide to diffuse through the same pot.

percentage of carbon in urea

Answers

The percentage of carbon in urea is [CO(NH 2) 2] is 20%

.hlp me to solve mcq​

Answers

Answer:

i) b

ii) c

Explanation:

Please see attached picture for full solution.

Which is the correct definition of metallic bonding? Select one: a. an array of positive ions in a sea of electrons b. complete transfer of valence electrons c. atoms share electrons to to be stable

Answers

Answer:

I believe it's A) an array of positive ions in a sea of electrons

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