Write an expression for standard enthalpy of formation using suitable chemical reaction

A strong force - called the strong nuclear force - holds protons and neutrons together in the nucleus.

Answer:

hope this helps!

Answer:

Explanation:

3: Given data:

Number of moles of strontium nitrate = 3.00×10⁻³ mol

Number of atoms = ?

Solution:

There are 9 moles of atoms in 1 mole of Sr(NO₃)₂.

In 3.00×10⁻³ moles,

9 mol × 3.00×10⁻³

27.00×10⁻³ mol

Number of atoms in 3.00×10⁻³ mol of Sr(NO₃)₂:

27.00×10⁻³ mol × 6.022×10²³ atoms / 1mol

162.59×10²⁰ atoms

4)Given data:

Mass of calcium hydroxide = 4500 Kg (4500/1000 = 4.5 g)

Number of moles = ?

Solution:

Number of moles = mass in g/molar mass

by putting values,

Number of moles = 4.5 g/ 74.1 g/mol

Number of moles = 0.06 mol

5) Given data:

Number of atoms of silver nitrate = 1.06×10²³

Number of moles = ?

Solution:

1 mole of any substance contain  6.022×10²³ atoms .

1.06×10²³ atoms × 1 mol /  6.022×10²³ atoms

0.176 moles of silver nitrate

Describe the characteristics of the water at the mountain source:

Answer:

The answer is below

Explanation:

Speed: there will be faster speed due to the steep slope movement of water from the mountain.

Temperature: there will be lower temperatures as a result of the faster speed of water movement which reduces the influence of solar radiation on it.

Oxygen: the oxygen content is higher due to little or no residue particles present in it.

Nutrient Level: this is considered somewhat low as a result of the water coldness and speed which does not support the nutrition base to form.

Answer:

c.  

Fluorine

Explanation:

Answer:

V = 44.83 L

Explanation:

Given data:

Volume of nitrogen gas = ?

Number of moles = 2.0 mol

Temperature = 0°C

Pressure = 1atm

Solution:

The given problem will be solve by using general gas equation,

PV = nRT

P= Pressure

V = volume

n = number of moles

R = general gas constant = 0.0821 atm.L/ mol.K  

T = temperature in kelvin

Now we will convert the temperature.

0+273 = 273 K

1 atm× V = 2.0 mol × 0.0821 atm.L/mol.K × 273K

1 atm× V = 44.83 atm.L

V = 44.83 atm.L / 1 atm

V = 44.83 L

NaBr(aq) + AgNO3(aq) →NaNO3(aq) + AgBr(s)⇒ double-replacement reactions will occur

Double-Replacement reactions. Happens if there is an ion exchange between two ion compounds in the reactant to form two new ion compounds in the product

A double replacement reaction will occur if one or both of the products is an insoluble precipitate, a liquid, or a gas

To predict whether this reaction can occur or not is one of them, the precipitation reaction. A precipitation reaction occurs if two ionic compounds which are dissolved reacted to produce one of the products of the ion compound does not dissolve. Formation of these precipitating compounds that cause reactions can occur

Solubility Rules:

• 1. soluble compound

All compounds of Li +, Na +, K +, Rb +, Cs +, and NH4 +

All compounds of NO₃⁻ and C₂H₃O₂⁻

Compounds of Cl−, Br−, I− except Ag⁺, Hg₂²⁺, Pb²⁺

Compounds of SO₄²⁻ except Hg₂²⁺, Pb²⁺, Sr²⁺, Ba²⁺

• 2. insoluble compounds

Compounds of CO₃²⁻ and PO₄³⁻ except for Compounds of Li +, Na +, K +, Rb +, Cs +, and NH₄ +

Compounds of OH− except Compounds of Li +, Na +, K +, Rb +, Cs +, NH₄⁺ , Sr²⁺, and Ba²⁺

NaBr(aq) + AgNO3(aq) →NaNO3(aq) + AgBr(s)⇒ occur

NaBr(aq) + Ca(NO3)2(aq) → NaNO3(aq) + CaBr₂(aq)⇒not occur

NaBr(aq) + Al(NO3)3(aq) →NaNO3(aq) + AlBr3(aq)⇒not occur

NaBr(aq) + KNO3(aq) →NaNO3(aq) + KBr(aq)⇒not occur

Answer:

Chloroplast.

Explanation:

Answer:

chlorophat

Explanation:

Answer: that should be true if not look it up :)

Explanation:

Answer:

igneous, sedimentary, and metamorphic

Explanation:

Answer:

IGNEOUS ROCKS form when molten rock (magma or lava) cools and solidifies. SEDIMENTARY ROCKS originate when particles settle out of water or air, or by precipitation of minerals from water.

And METAMORPHIC (I dont have nothing for this won)

Explanation:

Answer:c is correct

Explanation:

Answer:

[tex]\boxed {\boxed {\sf 0.0018 \ mol \ H_2 O }}[/tex]

Explanation:

First, we need to find the molecular mass of water (H₂O).

H₂O has:

Use the Periodic Table to find the mass of hydrogen and oxygen. Then, multiply by the number of atoms of the element.

There are 2 hydrogen atoms, so multiply the mass by 2.

Now, find the mass of H₂O. Add the mass of 2 hydrogen atoms and 1 oxygen atom.

Next, find the amount of moles using the molecular mass we just calculated. Set up a ratio.

[tex]0.032 \ g \ H_2 O* \frac{ 1 \ mol \ H_2 O}{18.0152 \ g \ H_2 O}[/tex]

Multiply. The grams of H₂O will cancel out.

[tex]0.032 * \frac{1 \ mol \ H_2 O}{18.0152 }[/tex]

[tex]\frac{0.032 *1 \ mol \ H_2 O}{18.0152 }[/tex]

[tex]0.00177627781 \ mol \ H_2 O[/tex]

The original measurement given had two significant figures (3,2). We must round to have 2 significant figures. All the zeroes before the 1 are not significant. So, round to the ten thousandth.

The 7 in the hundred thousandth place tells us to round up.

[tex]0.0018 \ mol \ H_2 O[/tex]

There are about 0.0018 moles in 0.032 grams.

Explanation:

Nuclear energy is found in the nucleus of an atom holding nuclear materials in place.

When a nuclear decay or fusion occurs, the energy is released.

Answer:

5

Explanation:

Answer:

250 collisions per square inch

Explanation:

According to Boyle's law, at constant temperatures, the pressure exerted by gas molecules is inversely proportional to the volume of the gas. Hence;

    P1V1 = P2V2 where P1 = initial pressure, V1 = initial volume, P2 = final pressure, and V2 = final volume

In this case, the collision that occurred is taken as the pressure.

P1 = 1250, V1 = 4.30 , V2 = 21.5 P2 = ?

P2 = P1V1/V2

        = 1250 x 4.30/21.5

                 = 250

Hence, at a constant temperature, 250 collisions per square inch of the larger container will occur.

Answer:

ture

Explanation:

trees, plants is what keeps us alive

Answer:

Ice cubes, glass of tea, and butter

Explanation:

Like it said in the hint, the molecules will only speed up if they gain heat. This means in order for the object to heat up it will have to have a temperature that is less than the temperature in the room. Ice cubes, glass of tea, and butter are the three objects that have a temperature less than 72 degrees so when they are placed in the 72 degrees room they will heat gain heat (therefore making the molecules move faster)

Answer:

Absorbs, Releases

Explanation:

The formation of an ionic compound involves the transfer of electrons. The removal of one or more electrons from a metal is a process that absorbs energy, whereas the addition of one or more electrons to a nonmetal releases energy.

Answer:

Absorbs

Release

Explanation:

The formation of ionic compounds occurs between two kinds of atoms having a large electronegativity difference (Δx ≥ 0.7) e.g metals (like those in group IA and IIA) and non-metals(like those in groups VIA and VIIA). The formation of an ionic bond involves the transfer of electron(s) from the less electronegative atom (metal) to the more electronegative atom (non-metal) such that the two kinds of atoms now have a completely filled outer shell like the noble gas.

Answer:

A través del Experimento de Rutherford.

Explanation:

El experimento de la lámina de oro fue realizado en 1909 por Ernest Marsden y Hans Geiger bajo el liderazgo de Ernest Rutherford. En este experimento, se bombardeó una lámina de oro con partículas alfa y se detectó su dispersión. Se encontró que una pequeña proporción de las partículas regresan cerca de la fuente. Estos resultados fueron la base para el lanzamiento de un nuevo modelo atómico con un núcleo central cargado positivamente y con electrones cargados negativamente con pequeñas masas en relación con el núcleo y distribuidos a su alrededor.

Answer:

Energy is neither created nor destroyed.

Explanation:

The law of conservation of energy states that energy can neither be created nor be destroyed. The total energy of an isolated system remains conserved. It never gets 0. It changes from one form of energy to other but never vanishes.

Hence, the correct option is (d) "Energy is neither created nor destroyed"

Answer:

Limitation of hydrogen displacement method​  is described below in detailed explanation.

Explanation:

This approach is beneficial for elements that can displace hydrogen from psychedelics or can consolidate with hydrogen. A single replacement effect, sometimes described as a single displacement reaction, is a reflection in which one component is replaced for a different component in a compound. The origin elements are forever pure elements, such as a clear zinc metal or hydrogen propellant, plus an aqueous compound.

Answer:

because they need only one electron

Answer: The atomic number indicates the number of protons within the core of an atom. The atomic number is an important concept of chemistry and quantum mechanics. An element and its place within the periodic table are derived from this concept. ... These electrons mainly determine the chemical behaviour of an atom. The chemical properties of an element, are determined by the number of protons in the nucleus. This number of protons is called the atomic number. The mass of the atom, its atomic mass, depends upon the sum of the number of protons and the number of neutrons present in the nucleus.

Hope this helps....... Stay safe and have a Merry Christmas!!!!!!! :D

Explanation:

Outer Electrons/Valence Electrons determine the chemical properties....Or Somehow we can say in organic compounds, functional group determine mostly chemical properties...

Answer:

The heat energy stored within them changes

Explanation:

Heat energy is a function of the mass of a body, its specific heat capacity, and its temperature.

In this case, the bodies have the same specific heat capacity since they are made from the same material and the same temperature.

To get the quantity of heat stored in a body, we need to multiply all three parameters as shown below

[tex]Q = mC \Delta T[/tex]

An increase in mass, through an increase in the amount of substance of a material present, will cause a corresponding increase in the heat energy stored within the material

Answer:

A. They include both oxidation and reduction reactions AND B. Electrons are transferred.

Explanation:

a p e x

The statements that are true about redox reaction are:

A. They include both oxidation and reduction reactions,

B. Electrons are transferred.

The Redox reaction is the one in which oxidation and reduction take place simultaneously. In this process transfer of electrons takes place which further leads to oxidation or reduction.

Thus, options A and B are correct.

Find more information about Redox reaction here:

brainly.com/question/21851295

Answer:

c

Explanation:

i think

Answer:

15.3 moles of CO₂ formed.

Explanation:

Given data:

Number of moles of CO₂ formed = ?

Number of moles of C₃H₈ react = 5.1 mol

Solution:

Chemical equation:

C₃H₈ + 5O₂       →     3CO₂ + H₂O

Now we will compare the moles of CO₂ with C₃H₈.

                          C₃H₈         :          CO₂

                              1            :            3

                             5.1          :         3/1×5.1 = 15.3 mol  

There are 1825.6 g in a 14.5 moles Lithium permanganate

The mole is the number of particles(molecules, atoms, ions) contained in a substance  

1 mol = 6.02.10²³ particles

Can be formulated

N=n x No

N = number of particles

n = mol

No = Avogadro's = 6.02.10²³

Moles can also be determined from the amount of substance mass and its molar mass :

[tex]\tt mol=\dfrac{mass}{MW}[/tex]

moles of Lithium permanganate = 14.5

Lithium permanganate (LiMnO4) MW=125.9 g/mol, so mass :

[tex]\tt mass=mol\times MW\\\\mass=14.5\times 125.9~g/mol\\\\mass=1825.6~g[/tex]

Answer:

For a given amount of gas held at constant temperature, the product of pressure and

volume is constant.

:

The answer i got was C so I would pick C