Calculate the average atomic mass for element X

Answer:

This reaction is exothermic because the system shifted to the left on heating.

Explanation:

2NO₂ (g) ⇌ N₂O₄(g)

Reactant => NO₂ (dark brown in color)

Product => N₂O₄ (colorless)

From the question given above, we were told that when the reaction at equilibrium was moved from room temperature to a higher temperature, the mixture turned dark brown in color.

This simply means that the reaction does not like heat. Hence the reaction is exothermic reaction.

Also, we can see that when the temperature was increased, the reaction turned dark brown in color indicating that the increase in the temperature favors the backward reaction (i.e the equilibrium shift to the left) as NO₂ which is the reactant is dark brown in color. This again indicates that the reaction is exothermic because an increase in the temperature of an exothermic reaction will shift the equilibrium position to the left.

Therefore, we can conclude that:

The reaction is exothermic because the system shifted to the left on heating.

The reaction is exothermic and the equilibrium position shifted to the left hand side.

An exothermic reaction is one in which heat is given out. Hence, the equilibrium position moves towards the left when the temperature is increased in an exothermic reaction.

Given the reaction, 2NO2(g) ⇌ N2O4(g) the appearance of a dark brown gas at high temperature implies that the reaction is exothermic and the equilibrium position shifted to the left hand side.

Learn more about exothermic reaction: https://brainly.com/question/15308590

Answer:

18.5g Na2CO3

Explanation:

Chromium (III) chloride, CrCl3, reacts with Na2CO3 as follows:

2CrCl3 + 3Na2CO3 → Cr2(CO3)3(s) + 6NaCl

Where 2 moles of CrCl3 react with 3 moles of Na2CO3 to produce 1 mole of Cr2(CO3)3 -The precipitate-

To solve this question we need to find the moles of CrCl3 added. With the chemical equation we can find the moles of Na2CO3 and its mass as follows:

Moles CrCl3:

520mL = 0.520L * (0.224mol/L) = 0.116 moles CrCl3

Moles Na2CO3:

0.116 moles CrCl3 * (3 mol Na2CO3 / 2mol CrCl3) = 0.175 moles Na2CO3

Mass Na2CO3 -Molar mass: 105.99g/mol-

0.175 moles Na2CO3 * (105.99g/mol) = 18.5g Na2CO3

Answer:

In after fasting test, Person 2 has slightly higher blood glucose level than person 1.

In after drinking glucose test, Person 3 has much high glucose level than person 1.

Explanation:

Blood sugar test determines the level of glucose present in body. The test can be taken after intake of food / glucose or after fasting for 12 hours. Results of both tests are compared to identify level of glucose present in human body. In after fasting test person has higher glucose and in another test person 3 has higher glucose level.

Answer:

3.90g/mL

Explanation:

To find the density of a substance, divide the mass by the volume.

So, 37.6 / 9.65 = 3.89637

then round to 3 significant figures

Good luck!

Answer:

An example of a chemical property of iron would be that it is capable of combining with oxygen to form iron oxide, or rust.

Explanation:

You have no choice listed, so I provided an example.

Explanation:

For both men and women, the basics of a balanced diet are the same. Men have higher caloric requirements than women since they have a bigger body (both in height and weight) and more muscular mass.

So, Men needs more energy.

50 year old woman require less energy than 50 year old man.​

Answer:

Nice and you

Explanation:

Please Mark me brainliest

Answer:

Todas son correctas

Explanation:

I) Los compuestos del carbono son solubles en disolventes no polares como el hexano, benceno, éter, etc. VERDADERO. La mayoría de los compuestos de carbono son apolares, y basados en la regla: Similar disuelve similar, podemos presumir que la mayoría de compuestos de carbono se disuelven en solventes no polares.

II) Los compuestos del carbono generalmente presentan puntos de fusión y de ebullición bajos. VERDADERO. Al ser sustancias apolares, sus fuerzas electrostáticas son bajas. De la misma manera, como su masa atómica es pequeña, las fuerzas de Van der Waals son despreciables haciendo que sus puntos de fusión y ebullición sean bajos respecto a sustancias de estrucutra similar.

III) La gran mayoría de los compuestos del carbono son combustibles, sean estos, gaseosos, líquidos o sólidos. VERDADERO. Los gases (Como el gas natural) son combustibles usados para cocina. Los líquidos (Como la gasolina) son combustibles y bastante inflamables. Los sólidos (Como la madera) se usan como combustibles para hacer asados o son el combustible en incendios forestales.

IV) El enlace covalente es característico de los compuestos del carbono. VERDADERO. La polaridad del carbono es neutral haciendo que la mayoría de los enlaces que forma sean covalentes.

Answer:  b) a chemical reaction between carbohydrates and oxygen to produce carbon dioxide, water, and heat energy

Explanation:

Based on the options, I assume that this is talking about the process of respiration. Respiration allows living things to produce energy by reacting carbohydrates with oxygen.

This results in the release of energy in the form of heat in a cell and also the formation of carbon dioxide and water. This type of respiration is known as Aerobic respiration.

Hi there!

[tex]\large\boxed{3.203 * 10^{22} atoms}[/tex]

We can use the following conversions to solve:

Total mass --> amount of mols --> amount of atoms (Avogadro's number)

Begin by calculating the amount of boron trifluoride in 3.61 grams:

3.61 g * (1 mol BF₃ / 67.8 g) ≈ 0.0532 mol BF₃

Use avogadro's number to convert:

0.0532 mol * 6.02× 10²³atoms / 1 mol = 3.203 × 10²² atoms

Answer:

8.3 × 10³ mL

Explanation:

Step 1: Calculate the mass of water that contains 100 mg of Pb

The concentration of Pb in the sample is 0.0012% by mass, that is, there are 0.0012 g of Pb every 100 g of water. The mass of water that contains 100 mg (0.100 g) of Pb is:

0.100 g Pb × 100 g Water/0.0012 g Pb = 8.3 × 10³ g Water

Step 2: Calculate the volume corresponding to 8.3 × 10³ g of water

Since the solution is diluted, we will assume the density of the sample is equal than the density of water (1 g/mL).

8.3 × 10³ g × 1 mL/1 g = 8.3 × 10³ mL

The volume of the water in milliliters contains 100 mg of Pb is;

V =  8.3 × 10³ mL

We are given the concentration of Pb in the sample as 0.0012% by mass.

That means that there are 0.0012 g of Pb in every 100 g of water.

Thus, the mass of water that contains 100 mg (0.100 g) of Pb is calculated as;

(0.100 g Pb × 100 g of Water)/0.0012 g of Pb = 8.3 × 10³ g of Water

Now, we know that the density of water (1 g/mL) but we are not given the density of the sample.

Thus, since the solution is diluted we can equally say that;

Density of sample = 1 g/mL

Formula for Volume is;

V = mass/density

Thus;

V = 8.3 × 10³ g/1 g/mL

V = 8.3 × 10³ mL

Read more about Volume of solution at; https://brainly.com/question/17055828

Answer:

CH3—CH2—O—CH2—CH3 is the compound of glycol.

Answer:

HOH2C―CH2―CH2―CH2OH is glycol

Explanation:

Answer:

Hi!

chemistry;

unlike others, is more about atomic structure.

HAVE A NİCE DAY

Explanation:

GREETİNGS FROM TURKEY ツ

Answer:

CHEMISTRY means the study of matter and the different chemical reactions that any substance goes through, like, matters composition, structure, shape, state, etc. while geology, biology and physics are the other branches of science and chemistry acts as a bridge between physics and geology with biology.

hope it helps

have a nice day

Answer:

D. 2

Explanation:

On the right side of the equation:

Al has 1, Zn has 3, NO3 has 6

But on the left side:

Al has 1, Zn has 1, NO3 has 3

1. So, if we add a coefficient of 2 to Al(NO3)3, then NO3 now has 6-which is what it needs.

2. But now the Al on the right side of the equation is not balanced, so give it a coefficient of 2.

3. To make the Zn balance, just add a coefficient of 3 on the left side of the equation.

Which leaves us with:

2Al + 3Zn(NO3)2 --> 2Al(NO3)3 + 3Zn

And now there are the same number of each compound on both sides of the equation.

Good luck! If you have any questions on this answer leave a comment :)

Answer:

C thermal

Explanation:

Answer:

Density of the solid=[tex]2.78 g/cm^3[/tex]

Explanation:

We are given that

Mass of sample of metal=4.369 g

Volume in the flask, V=126.4 ml

Mass of water, flask, and metal=268.5 g

Mass of flask=139.3 g

Density of water=1.000 g/mL

We have to find the density of the solid.

Mass of water=268.5-4.369-139.3=124.831 g

Volume of water=[tex]\frac{Mass\;of\;water}{density\;of\;water}[/tex]

Volume of water=[tex]\frac{124.831}{1}=124.831 mL[/tex]

Volume of solid=126.4 ml-124.831 mL

=1.569mL

Now,

Density of the solid=[tex]\frac{mass\;of\;solid}{volume\;of\;solid}[/tex]

=[tex]\frac{4.369}{1.569}[/tex]

[tex]=2.78g/mL[/tex]

1mL=1 cubic cm

Therefore,

Density of the solid=[tex]2.78 g/cm^3[/tex]

Answer:

0.5 M

Explanation:

From the question given above, the following data were obtained:

Mass of NaOH = 80 g

Volume of solution = 4 L

Molarity =?

Next, we shall determine the number of mole in 80 g of NaOH. This can be obtained as follow:

Mass of NaOH = 80 g

Molar mass of NaOH = 23 + 16 + 1

= 40 g/mol

Mole of NaOH =?

Mole = mass / molar mass

Mole of NaOH = 80 / 40

Mole of NaOH = 2 moles

Finally, we shall determine the molarity of the solution. This can be obtained as follow:

Mole of NaOH = 2 moles

Volume of solution = 4 L

Molarity =?

Molarity = mole / Volume

Molarity = 2/4

Molarity = 0.5 M

Therefore, the molarity of the solution is 0.5 M.

Answer:

B

pls correct me if im wrong

Answer:

positive force → balanced force → negative force

Explanation:

np

Answer:

positive force → balanced force → negative force

Explanation:

:)))

Explanation:

Science, any system of knowledge that is concerned with the physical world and its phenomena and that entails unbiased observations and systematic experimentation. In general, a science involves a pursuit of knowledge covering general truths or the operations of fundamental laws.

A reaction in which reduction and oxidation take place simultaneously known as a redox reaction.

Answer:

1) The percentage of oxygen in dry air is _______

C. 21

2) The composition of the Earth’s earliest atmosphere was different to that of the present atmosphere. Which of these gases was present in large amounts in the Earth’s earliest atmosphere?

B. CARBON DIOXIDE

Hope it helps

have a nice day

Answer: The percentage of oxygen in dry air is .  21

Explanation:  Ammonia gases was present in large amounts  in the easth7s earliest atmosphere

Hope it will help you

Answer:

4.. increases

5..lowers

6.. increases

7.. increases

8.. speed

Answer:

When a substance is heated, its temperature rises because its molecules move faster and gain thermal energy. Temperature measures the "hotness" or "coldness" of an object. The term heat refers to thermal energy being transferred from a hotter system to a cooler one.

Answer:

endothermic

Explanation:

endothermic reactions absorb heat from their surroundings, in this reaction the reactants are gas and solid and the products are liquid and gas, implying heat was absorbed to turn a solid to a liquid.

Answer: The general formulae for moles is n=m/mr so now we have being given to find the mass so all we have to do is to change subject

Explanation:  so we have to change subject in this question to m= n× mr . so in the question below we have being given the mole as 1.5mol/dm³  so all we have to do is to find the molecular relative mass(mr) .

to find the molecular relative mass of sodium hydroxide (NAOH) we add all of the atomic masses of all the atoms present so here we have sodium oxygen and hydrogen atoms present.

NA=23 O=16 H=1 so we add 23+16+1=40 so 40 is our molecular relative mass

now we fix it in our formulae which is m=n× mr

m=1.5× 40 =60 so our mass is 60grams or 60g

HOPE THIS HELPS!!!! if i made a mistake our MAY answer may be wrong feel free to comment

Answer:

Synthetic sponges are made of three basic ingredients: cellulose derived from wood pulp, sodium sulphate, and hemp fiber. Other materials needed are chemical softeners, which break the cellulose down into the proper consistency, bleach, and dye.

Explanation:

IDK, BUT HOPE IT HELPS?