Can someone plz help me :<

Answer:

½N 2(g) + O 2(g) + 8.1 kcal → NO 2(g)

½N 2(g) + ½O 2(g) → NO(g), ΔH = +21.6 kcal/mole

NH 3(g) → ½N 2(g) + 3/2H 2(g), ΔH = +11.0 kcal/mole

General Formulas and Concepts:

Thermochemistry

Explanation:

An endothermic reaction would have heat or energy gained in the final stage of the reaction.

This means that our enthalpy would be positive and heat/energy would be added as a reactant.

Out of all the answer choices, we see that only these have heat/energy added in the reactant side or the enthalpy being positive:

½N 2(g) + O 2(g) + 8.1 kcal → NO 2(g)

½N 2(g) + ½O 2(g) → NO(g), ΔH = +21.6 kcal/mole

NH 3(g) → ½N 2(g) + 3/2H 2(g), ΔH = +11.0 kcal/mole

Topic: AP Chemistry

Unit: Thermochemistry

Answer:

propene and hydrogen is product

When propanol is heated with concentrated sulphuric acid at 443 K, dehydration takes place and prop-1-ene is formed. In this reaction concentrated sulphuric acid acts as a dehydrating agent.

I. A + HCl gives )-gives 2-chloropropane

II. A --> Combustion ( what product does it form. Write out the equation propene ozonide

III.A ---> Hydrogenation (what product does it form. Write out the equation )propanol

Answer:

I would guess more atoms? but there is no graph attached

Answer:

the valency of an element is its combining capacity that is the number of electrons it requires to lose, gain or share in order to become neutral.

[ An element can become neutral if it completes it's octet. That is if an element has 8 electrons in it'd outermost shell then it is considered neutral ]

Hence they both have the same valence.

One may say that oxygen's valence is -2 while that of Magnesium is + 2. It's meaning is still the same but "-" sign indicates that oxygen will be gaining electrons in the process of becoming stable.

Answer:

This is because Mendeleev arranged the elements in order of increasing relative atomic mass.

Explanation:

Dmitri Mendeleev is one of the scientists that contributed to the development of periodic table in chemistry. He was able to organise elements into rows according to their atomic mass and into columns based on chemical and physical properties. This is the main reason why his periodic table is still studied even though it has some defects which include:

--> Grouping of elements that are not similar chemically: For example Copper and Silver bear no resemblance with the alkali metals, but they have been placed together in the first group.

--> Position of isotopes: According to his periodic table: Isotopes of an element must be given separate places in the periodic table because they have different atomic masses.

--> Electronic arrangement of elements: It failed to explain the electronic arrangement of elements.

--> Separation of chemically similar elements:

Elements that are chemically similar such as Gold and Platinum have been placed in separate groups.

Answer:

NH4+

Explanation:

NH4+ is the acid and NH3 is the base, so NH4+ is the stronger acid.

Answer:

A. 70 K

B. 3.16 atm

Explanation:

We'll begin by calculating the number of mole in 175 g of Ar. This can be obtained as follow:

Mass of Ar = 175 g

Molar mass of Ar = 40 g/mol

Mole of Ar =?

Mole = mass / molar mass

Mole of Ar = 175 / 40

Mole of Ar = 4.375 moles

A. Determination of the temperature.

Mole of Ar (n) = 4.375 moles

Volume (V) = 2.50 L

Pressure (P) = 10 atm

Gas constant (R) = 0.0821 atm.L/Kmol

Temperature (T) =?

PV = nRT

10 × 2.5 = 4.375 × 0.0821 × T

25 = 4.375 × 0.0821 × T

Divide both side by (4.375 × 0.0821)

T = 25 / (4.375 × 0.0821)

T ≈ 70 K

B. Determination of the pressure.

Mole of Ar (n) = 4.375 moles

Volume (V) = 2.50 L

Temperature (T) = 22 K

Gas constant (R) = 0.0821 atm.L/Kmol

Pressure (P) =?

PV = nRT

P × 2.5 = 4.375 × 0.0821 × 22

Divide both side by 2.5

P = (4.375 × 0.0821 × 22) / 2.5

P = 3.16 atm.

Answer:

I think option (d) is right answer

Answer:

I think that the answer is option(C)

Answer:

FOUR HYDROGEN ATOMS

Explanation:

Two C atoms, four H atoms, and two O atoms can also be arranged to form a methyl formate, which is used in manufacturing, as an insecticide, and for quick-drying finishes. Methyl formate molecules have one of the oxygen atoms between the two carbon atoms, differing from the arrangement in acetic acid molecules.

The Methylene group has 2 hydrogen. -CH2

Answer:

1. To be able to easily name organisms

2. To ease communication among scientists

3. To give knowledge about the broad variety of organisms

4. To make the study of organisms easier

The answer is ‘Passive Transport’

movement of molecules without the use of energy is due to the shrinkage of water

Answer:

yes it does

Explanation:

because the ratios on the reactants and products are equal

The reaction 2Na(s) + Cl₂(g) → 2NaCl(s) obeys the law of conservation of mass.

Yes, this reaction obeys the law of conservation of mass. The law of conservation of mass states that mass is neither created nor destroyed in a chemical reaction; it is only rearranged.

In the given reaction, we have 2 sodium atoms (Na) on the left side and 2 sodium atoms (Na) on the right side. Similarly, we have 2 chlorine molecules (Cl₂) on the left side and 2 chlorine atoms (Cl) on the right side. Therefore, the number of atoms of each element is balanced on both sides of the reaction.

Additionally, the total mass of the reactants (2Na + Cl₂) is equal to the total mass of the product (2NaCl). The coefficients in the balanced equation represent the stoichiometric ratios, ensuring that the mass is conserved.

Hence, the reaction 2Na(s) + Cl₂(g) → 2NaCl(s) obeys the law of conservation of mass.

Learn more about law of conservation of mass from the link given below.

https://brainly.com/question/28711001

#SPJ2

Answer: It’s 4.0

Explanation: I just took the test and got it right:)

Answer:

phloem I believe

Explanation:

dictionary

Answer:

= P + 2eF + N + S + 6gM + 2

Explanation:

Multiply: 1 . N = N

= P + 2eF + N + 1 . S + 6gM + 2

Multiply: 1 . S = S

= P + 2eF + N + S + 6gM + 2

Hope This Helps!

Answer:

the atomicity of sulphur is 8

Explanation:

hope it helps

Answer:

A chemical property is a characteristic of a substance that may be observed when it participates in a chemical reaction. Examples of chemical properties include flammability, toxicity, chemical stability, and heat of combustion

Answer:

carbon monoxide

I think its correct but I am not sure

Answer: when carbon is heated in air carbon dioxide is formed, so is incomplete combustion which results in carbon monoxide.

Explanation: but when carbon dioxide reacts with more oxygen carbon monoxide is formed i guess.

I AM A BIT SURE BUT HOPE THIS HELPSSSS!!!!

Answer:

What is the question needing to be answered?

Explanation:

Usually with a scientific hypothesis, you ask the question in an if, then statement. For example: If it rains outside, then the ground will be wet. It's kind of like a cause and effect statement.

Answer: The answer is they are not closely packed

Explanation: HOPE THIS HELPS!!

Answer:

Yes a chemical reaction is taking place.

Explanation:

There is a change in temperature along with bubbling. All signs of a chemical reaction.

Answer:

B or C think so

Answer:

we will solve your Quiz

Explanation:

kindly contact us for your chemistry QUIZ and BOOK it with us at gotit pro

Answer:

D

Explanation:

B is solid and liquid while D is liquid and gas

Answer:

Option ( D) is correct

The phase transition occurs at 100o C (the normal boiling point of water). Liquid water becomes water vapor or steam when it enters the gaseous phase.

Explanation:

A heating curve graphically represents the phase transitions that a substance undergoes as heat is added to it.

The liquid will begin to boil when enough heat has been absorbed by the solution that the temperature reaches the boiling point, where again, the temperature remains constant until all of the liquid has become gaseous water. At the atmospheric pressure of 1 atm, this phase transition occurs at 100o C (the normal boiling point of water). Liquid water becomes water vapor or steam when it enters the gaseous phase. Use the heat of vaporization ([latex]\Delta H_{vap}[/latex] ) to calculate how much heat was absorbed in this process: [latex]q=m\cdot C_{H_2O(g)}\cdot \Delta T[/latex], where m is the mass of the sample of water.

After all of the liquid has been converted to gas, the temperature will continue to increase as heat as added. Again, the heat added that results in a certain change temperature is given by: [latex]q=m\cdot C_{H_2O(g)}\cdot \Delta T[/latex] . Note that the specific heat capacity of gaseous water is different than that of ice or liquid water.

Answer: the atomic size will decrease

Explanation:

Answer:

It will remain the same because it is moving up and down to and fro it can not increase nor decrease or else will become an ion

Answer:

The number of hydrogen atoms is 4.96x10²⁴.

Explanation:

The number of atoms can be found with the following equation:

[tex] n = N*\eta_{H} [/tex]

Where:

N: is the Avogadro's number = 6.022x10²³ atoms/mol

η: is the number of moles of hydrogen

n: is the number of hydrogen atoms

First, we need to find the number of hydrogen moles. The number of moles of CH₄ is:

[tex] \eta_{CH_{4}} = \frac{m}{M} [/tex]

Where:

m: is the mass of methane = 33 g

M: is the molar mass of methane = 16.04 g/mol                      

[tex] \eta_{CH_{4}} = \frac{33 g}{16.04 g/mol} = 2.06 mol [/tex]

Now, since we have 4 hydrogen atoms in 1 mol of methane, the number of moles of hydrogen is:

[tex] \eta_{H} = 2.06\: mol\: CH_{4}*4 \frac{mol\: H}{mol \: CH_{4}} = 8.24 mol [/tex]

Hence, the number of hydrogen atoms is:

[tex]n = N*\eta_{H} = 6.022 \cdot 10^{23} \: atoms/mol*8.24 mol = 4.96 \cdot 10^{24} atoms[/tex]

Therefore, the number of hydrogen atoms is 4.96x10²⁴.

I hope it helps you!      

Answer:

NAO SRESONDEPORR PQUEOU BUOBRRRA  IGAD THCAAUSEI

Explanation: