Identify the formula for the binary covalent compound,
phosphorus pentabromide.

A.
PBr5
B.
PBr5
C.
5PBr
D.
P5Br

Answer is: 1.6 liters of NO are produced.

Balanced chemical reaction: 4NH₃ + 5O₂ → 4NO + 6H₂O.

V(O₂) = 2.0 L; volume of oxygen.

From balanced chemical reaction: n(O₂) : n(NO) = 5 : 4.

V(O₂) : V(NO) = n(O₂) : n(NO).

2.0 L : V(NO) = 5 : 4.

V(NO) = 2 L · 4 ÷ 5.

V(NO) = 1.6 L; volume of nitrogen (II) oxide.

Answer:

q = -39.8 kJ

Step-by-step explanation:

CH₃OH(g) ⇌ CH₃OH(l); ΔH(cond) = -35.2 kJ·mol⁻¹

(1) Calculate the moles of methanol

n = 36.2 × 1/32.04

n = 1.130 mol

=====

(2) Calculate the heat evolved

q = nΔH(cond)

q = 1.130 × (-35.2)

q = -39.8 kJ

Answer:

Single bond between two carbon atoms.

Explanation:

Let us look at the structure of a hexagon for representation of cyclohexane.

Cyclohexane has six carbons and thus we can place each carbon at the vertices of the hexagon. Now the bond joining each adjacent carbon atoms will be shown by the each side of the hexagon.

The hydrogen atoms are not shown in the structure.

Answer:

Single bond between two carbon atoms.

Explanation:

Hi my dear friend,

Changes of state involve a solid melting, a liquid freezing, a liquid boiling or a gas condensing. When steam, which is gaseous water, condenses, heat is released. Likewise when liquid water freezes, heat is given off. In fact heat must be continually removed from the freezing water or the freezing process will stop.

~Thank you

Answer: The angle between the carbon-chlorine bonds in phosgene will be 120°

Explanation: Formula used to calculate the hybridization:

[tex]{\text{Number of electron pairs}} =\frac{1}{2}[V+N-C+A][/tex]

where,

V = number of valence electrons present in central atom i.e. carbon = 4

N = number of monovalent atoms bonded to central atom = 2

C = charge of cation = 0

A = charge of anion = 0

For [tex]COCl_2[/tex]

[tex]{\text{Number of electron pairs}} =\frac{1}{2}[4+2-0+0]=3[/tex]

The number of electron pairs are 3 which means that the hybridization will be [tex]sp^2[/tex] and the electronic geometry of the given molecule will be trigonal planar.

The bond angle in this electronic geometry is 120°

The structure of phosgene is attached below.

The angle between the Carbon-Chlorine bonds in the Phosgene molecule (COCl₂) is generally 120 degrees due to the sp² hybridization of the Carbon Atom

The phosgene molecule (COCl₂) has a planar shape, with the oxygen atom in the center, bonded to the carbon atom, and the chlorine atoms bonded to either side of the carbon atom. This creates a molecule with a structure in the shape of the letter 'V'. The angle between the carbon-chlorine bonds in the phosgene molecule is typically 120 degrees. This is due to the fact that the carbon atom in the center is sp² hybridized, meaning it has three regions of electron density spread out in a plane, forming angles of 120 degrees with each other.

https://brainly.com/question/11771189

#SPJ3

Use Raoult's Law and Henry's Law to calculate the activities and activity coefficients of substances a and b

To calculate the activities and activity coefficients of substances a and b, we can use Raoult's Law for substance a and Henry's Law for substance b.

The activity of substance a can be calculated using:

a = a/*a

The activity of substance b in terms of mole fraction can be calculated using:

b = b/*b

The activity coefficient of substance a can be calculated using:

a = a/Xa

The activity coefficient of substance b can be calculated using:

b = b/Xb

https://brainly.com/question/33890128

#SPJ3

As a comet approaches the Sun, it starts to heat up. The ice transforms directly from a solid to a vapor, releasing the dust particles embedded inside. Sunlight and the stream of charged particles flowing from the Sun – the solar wind – sweeps the evaporated material and dust back in a long tail.

Answer:

Comets are composed of ice, dust and frozen gases. The core of the comet is known as nucleus which is formed of rocks and frozen gases. Coma is the atmosphere of the comet. As the comet enters the inner solar system, the coma expands due to sublimation of frozen gases. As it nears the sun, the coma extends backwards and forms a long tail. It extends backwards due to the solar wind. The charged particles from the sun take away the evaporated material and dust of the comet backwards forming tail.

your element would be calcium

Answer: Option (A) is the correct answer.

Explanation:

Braising means first of all fry a dish slightly and then cook it slowly in a closed vessel or dish. The vessel is close so that the liquid present inside it does not evaporates.

Also, Braising is done to mix the flavors of different liquids or spices appropriately.  

Thus, we can conclude that as a cooking method, braising is valued for its ability to retain flavor.

Answer:

The correct answer is D.

Explanation:

This method of cooking is economical because it allows the use of common cuts, it is efficient because it allows to prepare the food in a single pot. The preparation is simple as it does not require an elaborate preparation. The meat is cooked in a pot, seasoned from the beginning, and there is no need to intervene in the process.

Have a nice day!

If you need the answer to this problem you need to post more information about the problem.

Answer:

Pair A: B

Pair B: A

Pair C: B

Answer: The correct option is Aluminium.

Explanation: To recover copper from the solution, we require a metal which can easily displace copper from the solution.

The reactions in which metal displaces another metal in a chemical reaction are known as single displacement reactions. These reactions are studied using reactivity series.

[tex]A+BC\rightarrow AC+B[/tex]

A is more reactive than B.

The metal which lie above in the reactivity series will easily displace the metal which lies below in the reactivity series.

From the given options, Aluminium is the most reactive of all the metals and hence, it is the best choice for recovering copper from its solution.

The  grams of  carbon   monoxide  that are needed to react   is  148.68 grams

  calculation

Step 1: find the   moles of iron

 moles =mass÷  molar mass

from periodic table the molar mass  of Fe  is 56 g/mol

= 198.5 g÷ 56 g/mol =3.54 moles

Step 2: use the mole  ratio  to determine the  moles  of  carbon monoxide(Co)

that is from  given equation Co : Fe  is 3:2  therefore the  moles of Co

= 3.54 x 3/2 = 5.31  moles

Step 3 : find mass of CO

mass = moles ×  molar mass

from periodic table  the molar mass  of Co = 12+16 = 28 g/mol

mass is therefore = 5.31 moles × 28 g/mol = 148.68  grams

Answer: The correct answer is C.

Explanation: Frictional force is the contact force which resists the motion of one surface on another.

Mathematically,

[tex]f=\mu N[/tex]

where,

f = frictional force

[tex]\mu[/tex] = Coefficient of friction

N = normal force acting on a body

We need to find the ratio of force of sliding friction ( which is a type of frictional force) and the normal force acting on an object. This will be equal to coefficient of friction.

[tex]\mu=\frac{f}{N}[/tex]

Answer:

weakest to strongest

Explanation:

Covalent bonding is an intramolecular interactions that hold the atoms together. Dispersion forces, hydrogen bonding and dipole-dipole interactions are intermolecular interactions . Intramolecular interactions are stronger than intermolecular interactions .

Dipole-dipole interactions occur when the partially positively charged part of a molecule interacts with the partially negatively charged part of the neighboring molecule. They are relative strong.

Hydrogen bonding is a special kind of dipole-dipole interaction that occurs specifically between a hydrogen atom bonded to either an oxygen, nitrogen, or fluorine atom. It is the strongest dipole-dipole interaction.

Dispersion forces  exist between all types of molecules, whether ionic or covalent (polar or nonpolar). They are the weakest of the intermolecular forces.

Answer: Formation of precipitate indicates that there has been a chemical reaction.

Explanation:

Chemical reaction:  It is defined as change in arrangement of the atoms so as to form a new substance.

Mixing of two clear solutions that is lead nitrate and potassium iodide gives out yellow solid precipitate of lead iodide with aqueous solution of potassium nitrate.

[tex]Pb(NO_3)_2(aq)+2KI(aq)\rightarrow PbI_2(s)+2KNO_3(aq)[/tex]

The physical evidence which indicates that chemical reaction has been taken place is formation of yellow solid precipitate of lead iodide ,([tex]PbI_2[/tex]).

 The percent yield  is 83.12%

  calculation

percent yield =  actual  yield / theoretical  yield x 100

actual yield =125.1 g

Theoretical yield  is calculated as below

Step 1:  find the  moles of MgCl₂

moles  = mass÷ molar mass

from periodic table the  molar mass of mgCl₂ =24.3 +(35.5 x2) =95.3 g/mol

moles = 50.0 g÷ 95.3 g/mol =0.525  moles

Step 2:  use the mole ratio to determine the moles of AgCl

from given equation MgCl₂: AgCl  is  1:2

therefore the moles of AgCl = 0.525  x2/1 =1.05 moles

Step 3: find the theoretical mass  AgCl

mass = moles x molar mass

from periodic table the molar mass of Agcl = 107.87 +35.5 =143.37 g/mol

mass = 1.05 moles x 143.37 g/mol =150.5 grams

The percent  yield  is therefore = (125.1 g/150.5)  x 100 = 83.12%

The answer is 9 please rate 5 ⭐️ if it was helpful.

1C5H10 + 15/2O2 => 5CO2 + 5H2O

Explanation:

Balanced equation is defined as the equation which contains same number of atoms on both reactant and product side.

For example, [tex]C_{5}H_{10}(l) + O_{2} \rightarrow CO_{2}(g) + H_{2}O(g)[/tex]

Number of atoms on reactant side are as follows.

Number of atoms on product side are as follows.

So, to balance this equation we will multiply [tex]CO_{2}[/tex] on product side by 5 and also multiply [tex]H_{2}O[/tex] by 5. On the reactant side, we multiply [tex]O_{2}[/tex] by  [tex]\frac{15}{2}[/tex]. Therefore, the balanced equation is as follows.

      [tex]C_{5}H_{10}(l) + \frac{15}{2}O_{2} \rightarrow 5CO_{2}(g) + 5H_{2}O(g)[/tex]

Thus, we can conclude that for the given unbalanced equation the coefficient for [tex]C_5H_10[/tex] is 1.

Answer: 5 moles of [tex]CO_2[/tex] will be produced when 10 moles  of [tex]H_2O[/tex] are produced.

Explanation:

[tex]CH_4+2O_2\rightarrow CO_2+2H_2O[/tex]

Multiplying the chemical equation with 5.

[tex]5CH_4+10O_2\rightarrow 5CO_2+10H_2O[/tex]

In the given reaction ,if 10 moles of water are produced then 5 moles of Carbon-dioxide produced.

Answer:

5

Explanation:

Answer is: the total number of electrons shared between the atoms is four.

Molecule of oxygen is nonpolar because double linear bonds (O=O).

Oxygen (O) is an element with atomic number 8, it means it has eight protons and eight electrons, so atom has neutral charge. Oxygen is a nonmetal.

Electron configuration of oxygen atom: ₈O 1s² 2s² 2p⁴.

Oxygen atom has six valence electrons, so it is in 16 group of Periodic table of elements.

Two valence electrons from both oxygen atoms form double bond (O::O) at oxygen molecule.

Answer:

Formula for oxygen is [tex]O_{2}[/tex] and total number of electrons shared between the atoms are 4

Explanation:

Oxygen is a diatomic molecule. Hence two oxygen atoms combine to produce one oxygen molecule.

Now, number of valence electron in a oxygen atom is 6. So total number of valence electrons used to form oxygen molecule are 12.

To draw a Lewis structure for [tex]O_{2}[/tex], octet rule should be fulfilled by both oxygen atoms.

According to octet rule, an atom should have 8 electrons in its valence shell

Lewis structure for oxygen molecule has been attached below.

Here electrons shared by oxygen atoms are represented as vertical line. These are called bonding electrons.

Unshared electrons are represented by dot. These are called lone pairs.

Here one bond is formed by sharing two electrons.

As there are two bonds between two oxygen atoms therefore total number of shared electrons between oxygen atoms are 4.

Condensation is the reverse change of evaporation.

The phase that is the reverse of evaporation is Condensation.

It is the process by which gas is cooled to any temperature above it freezing point to make it into liquid form.

Answer: Option (b) is the correct answer.

Explanation:

When the student is using beads then he is representing atoms and the straws represent the bond between the atoms.

Therefore, when a model is represented by the given manner then it helps in identifying the geometry or shape of the object. This is because it shows how atoms are arranged in space along with their angle.

Therefore, we can conclude that out of the given options the type of scientific model created by the student is a 3-dimensional model because it helps visualize the shape of the molecule.

The type of scientific model created by the student has been the 3-D model for the visualization of shape. Thus, option B is correct.

The water molecule has been the simplest compound that has been consisted of the two hydrogen atoms bonded with an oxygen atom.

The presence of loan pairs to the oxygen atom has been responsible for the distortion in the linear shape, and the molecule has been present in the inverted geometry.

The model prepared by the student has black beads as the representation of the hydrogen atoms, while white beads as the representation of the oxygen atom. The straws have been the representation of the bonds in the structure.

The model prepared has been capable of demonstrating the arrangement of the elements in the 3-D plane and has been able to elucidate the structure of the molecule. Thus, option B is correct.

For more information about the scientific model, refer to the link:

https://brainly.com/question/1622233

Answer :

Part (a) :  [tex]3H_2(g)+N_2(g)\rightarrow 2NH_3(g)[/tex]

Part (b) :  Theoretical yield of [tex]NH_3[/tex] = 440.96 g

Part (c) : Percentage yield of ammonia is 90.03 %

Mass of [tex]N_2[/tex] = 475 g

Molar mass of [tex]N_2[/tex] = 28 g/mole

Molar mass of [tex]NH_3[/tex] = 17 g/mole

Experimental yield of [tex]NH_3[/tex] = 397 g

Part (a) :The balanced chemical reaction will be:

[tex]3H_2(g)+N_2(g)\rightarrow 2NH_3(g)[/tex]

Part (b) :To calculate the moles of [tex]N_2[/tex]:

[tex]\text{Moles of }N_2=\frac{\text {Mass of }N_2}{\text{ Molecular mass of }N_2}=\frac{475g}{28g/mole}=16.96moles[/tex]

From the given balanced equation:

1 mole of [tex]N_2[/tex] gas produces 2 moles of [tex]NH_3[/tex]

16.96 moles of [tex]N_2[/tex] gas produces [tex]\frac{2}{1}\times 16.96=33.92[/tex] moles of [tex]NH_3[/tex]

Now we have to calculate the mass of [tex]NH_3[/tex]

[tex]\text{ Mass of }NH_3=\text {Moles of }NH_3\times \text{ Molar mass of }NH_3[/tex]

[tex]\text{ Mass of }NH_3=(33.92moles)\times (17g/mole)=440.96g[/tex]

Therefore, the theoretical yield of [tex]NH_3[/tex] gas = 440.96 g

Part (c) : Percentage yield :

[tex]\% \text{ yield of }NH_3=\frac{\text {Experimental yield of NH_3}}\text {Theoretical yield of }NH_3\times 100[/tex]

[tex]\% \text{ yield of }NH_3=\frac{397g}{440.96g}\times 100=90.03\%[/tex]

Therefore, the % yield of ammonia is 90.03 %

I have done some research as well as asking some friends. This is what I came up with. Not sure if it is 100% correct.

step = time after death

1. Livor Mortis = 20-30 minutes

2. Eyes film (cloud) = 2 hours

3. Rigor Mortis begins = 4-6 hours

4. Empty small intestines = 12 hours

5. Bloating = 3-5 days

6. Decay

Forensic scientists determine the time of death initially by observing physical changes such as the heart stopping, greying of the skin, cell death, muscle relaxation, and the emptying of the bladder and bowels. The sequence of these events helps establish a timeline. Additional factors like insect activity, weather conditions, and the setting may further assist in making an accurate estimation.

Forensic scientists, specifically forensic anthropologists and forensic pathologists, determine the time of death by analyzing various changes that occur in the body after death. These changes occur in a specific sequence and at different rates, thereby providing a means to estimate the time of death. The sequence of changes are as follows:

In addition to these changes, forensic scientists also study other evidence such as insect activity, weather conditions and surroundings to calculate the postmortem interval or to validate their findings based on the body's changes.

https://brainly.com/question/39067889

#SPJ12

A) I or Iodine

Iodine is solid which will be in a more fixed position and held closer together making it harder to break apart. It has more electrons and therefore more van der waals forces acting on it, which require more energy to break apart.

answer: a. I

explanation: iodine is a solid meaning the particles are closer together and holds a more fixed position, making it harder to break apart unlike a liquid or gas where the particles are more spread apart

The answer is B as isotopes are different versions of the same chemical element containing the same amount of protons and electrons but different amounts of neutrons.

Here is the answer!!! Just fill in the blanks.