PLEASE HELP WILL GIVE BRAINLIEST

 PLEASE HELP WILL GIVE BRAINLIEST

Answers

Answer 1

Answer: B

We use stoichiometric amounts of P4 and PH3

NO.9) It's actual yield

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Related Questions

1.86 g of ethanol reacts with 10.0 g of oxygen. What is the total volume of gas present (in L) after the reaction is complete, assuming the reaction takes place at 1.00 atm and 25oC?

Answers

Answer:

See explanation

Explanation:

The equation of the reaction is;

C 2 H 6 O(l)  +  3 O 2 (g)  → 2 CO 2 ( g )  +  3 H 2 O(l )

Next we have to determine the limiting reactant, this reactant gives the least number of moles of product.

Number of moles of C 2 H 6 O = mass/molar mass = 1.86g/ 46.07 g/mol = 0.04 mols

From the equation;

1 mol of ethanol yields 2 mols of CO2

0.04 moles of ethanol yields 0.04 * 2/1 = 0.08 mols of CO2

For water;

1 mol of ethanol yields 3 mols of water

0.04 moles of ethanol yields 3 * 0.04/1 = 0.12 mols of water

Also;

Number of moles of oxygen= 10g/32g/mol = 0.31 moles

3mols of O2 yields 2 moles of CO2

0.31 moles of O2 yields 0.31 * 2/3 = 0.21 moles of CO2

For water;

3 moles of O2 yields 3 moles of water

0.31 moles of O2 yields 0.31 * 3/3 = 0.31 moles of water

Hence ethanol is the limiting reactant.

From  PV=nRT

Volume of CO2 is;

V = nRT/P

V = 0.08 * 0.082 *298/1 = 1.95 L

Volume of water;

V = nRT/P

V= 0.12 * 0.082 * 298/1

V= 2.93 L

Total volume of gases after reaction = 1.95 L + 2.93 L = 4.88 L

When a magnesium bromide solution is mixed with a lead(II) nitrate solution, a precipitate forms. Determine the balanced molecular equation, the
complete ionic equation, and the net ionic equation.

Answers

Reaction :

MgBr₂(aq) + Pb(NO₃)₂(aq) → PbBr₂(s) + Mg(NO₃)₂(aq)

Further explanation

The electrolyte in the solution produces ions.

The equation of a chemical reaction can be expressed in the equation of the ions

For strong electrolytes (the ionization rate = 1) is written in the form of separate ions, while the weak electrolyte (degree of ionization <1) is still written as an un-ionized molecule

In the ion equation, there is a spectator ion that is the ion which does not change (does not react) because it is present before and after the reaction

When these ions are removed, the ionic equation is called the net ionic equation

For gases and solids including water (H₂O) can be written as an ionized molecule

A molecular equation is a chemical equation expressed as a molecule

So only the dissolved compound is ionized ((expressed in symbol aq)

Reaction

The balanced molecular equation

MgBr₂(aq) + Pb(NO₃)₂(aq) → PbBr₂(s) + Mg(NO₃)₂(aq)

The  complete ionic equation

Mg²⁺(aq)+2Br⁻(aq) + Pb²⁺(aq)+2NO₃⁻(aq)⇒PbBr₂(s) + Mg²⁺(aq)+2NO₃⁻(aq)

spectator ions : Mg²⁺(aq) and 2NO₃⁻(aq)

The net ionic equation (remove the spectator ions)

2Br⁻(aq) + Pb²⁺(aq)⇒PbBr₂(s)

The balanced molecular equation:

MgBr₂(aq) + Pb(NO₃)₂(aq) → PbBr₂(s) + Mg(NO₃)₂(aq)

The  complete ionic equation:

Mg²⁺(aq)+2Br⁻(aq) + Pb²⁺(aq)+2NO₃⁻(aq)⇒PbBr₂(s) + Mg²⁺(aq)+2NO₃⁻(aq)

The net ionic equation

2Br⁻(aq) + Pb²⁺(aq)⇒PbBr₂(s)

Balanced molecular reaction:

A chemical equation in which the number of each type of atom is equal on the two sides of the equation. Subscripts - Part of the chemical formulas of the reactants and products that indicate the number of atoms of the preceding element. A reaction that contains the stoichiometric ratios of the reactants and products; these ratios can be used for mole -to-mole conversions.

Thus, the reactions when a magnesium bromide solution is mixed with a lead(II) nitrate solution, a precipitate forms is given above.

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A gas is brought to a final pressure of 6.8 atm. after increasing its temperature from 40 K to 280 K. Calculate the original pressure of the gas.

Answers

Answer:

0.97 atm.

Explanation:

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

Final pressure (P2) = 6.8 atm

Initial temperature (T1) = 40 K

Final temperature (T2) = 280 K

Initial pressure (P1) =?

Thus, we can obtain the initial (original) pressure of the gas as follow:

P1/T1 = P2/T2

P1 /40 = 6.8/280

Cross multiply

P1 × 280 = 40 × 6.8

P1 × 280 = 272

Divide both side by 280

P1 = 272/280

P1 = 0.97 atm

Therefore, the original pressure of the gas is 0.97 atm.

For calcium-42, How many protons,
neutrons and electrons are present,
respectively.
A. 20, 42, 20
B. 20, 22, 20
C. 20, 22, 18
D. 42, 20, 20

Answers

Answer:

B. 20, 22, 20

Explanation:

The atomic number (Z) of calcium is 20, that is, it has 20 protons.

The mass number (A) of calcium-42 is 42. The mass number is equal to the sum of protons and neutrons. Then,

p⁺ + n⁰ = 42

n⁰ = 42 - p⁺

n⁰ = 42 - 20

n⁰ = 22

Since calcium is electrically neutral, it has the same number of protons (+) and electrons (-). Then, calcium has 20 electrons.

Experiment: Turn on Show electronegativity. Electronegativity (EN) describes how strongly an atom attracts a pair of shared electrons. The higher the EN value, the greater the tendency of an atom to hold onto electrons in a bond and become negatively charged. Electronegativity difference is found by subtracting the EN value of one atom from another. Choose two nonmetals with a small (or no) EN difference between them. Click Play. What happens to the shared electrons in this bond

Answers

Answer:

See explanation

Explanation:

If we take two nonmetals with little or no electronegativity difference between them, the shared electrons are not attracted greatly towards any of the bonding atoms. In other words, the shared electrons remain equidistant between the nuclei of the two bonding atoms.

The bond is nonpolar since polarity is introduced into covalent bonds by a significant difference in electronegativity of the bonding atoms.

What happens to molecular energy(heat) in water when water vapor becomes a liquid?
Group of answer choices
Water vapor gives up heat energy.

Water vapor absorbs heat energy.

As water's mass increases it absorbs energy.

Water vapor retains the same heat energy.

Answers

Answer:

Water vapor retains the same heat energy.

Answer:

water vapor gives up heat energy.

Explanation:

Took a quiz and got it right

Will give brainliest

Answers

I will help you with answering this question.

A certain reaction requires 0.250 moles of Na2SO4. How
much sodium sulfate should the chemist weigh out to perform
the reaction?

Answers

The chemist weigh out 35.51 g Na2SO4

Further explanation

Given

0.250 moles of Na2SO4

Required

weight of Na2SO4

Solution

A mole is a number of particles(atoms, molecules, ions)  in a substance

This refers to the atomic total of the 12 gr C-12  which is equal to 6.02.10²³, so 1 mole = 6.02.10²³ particles  

Moles of a substance can also be determined from its molecular weight

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

For 0.250 moles of Na2SO4, mass =

[tex]\tt mass=mol\times MW\\\\mass=0.25\times 142,04 g/mol\\\\mass=35.51~g[/tex]

All of these are types of slime except

A cornstarch slime.
B algal slime.
C slime molds.
D bacterial slime.

Answers

Answer:

imma say slime molds

Explanation:

if I'm wrong please tell me

Answer:

algal slime i think

Explanation:

anyways i passed my chemistry final yall. yupp

Answers

Explanation:

CONGRATULATIONS!!!!!

Answer:

chemistary more lliek dumastry ahaha

Explanation:

Which compound would you expect to be soluble in the nonpolar solvent carbon disulfide?

Answers

Answer:

hexane C6H14

IS YOUR ANSWER

Explanation:

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An elemental metal contains how many types of atoms?
a. 1
b. 2
c. 3
d. 4

Answers

Answer:

a

Explanation:

all elemental metals are made up of only one type of element

Answer:

It is 1.

Explanation:

Which activity is an example of chemical change?

Answers

An old penny rusting, remember you can’t undo a chemical change

Q 16.1: Select the first step in the Wittig reaction. A : The alkyltriphenylphosphonium halide is deprotonated by a base to make a phosphorus ylide. B : The phosphorus ylide reacts with the aldehyde or ketone to make an oxaphosphetane. C : Triphenylphosphine attacks the alkyl halide to produce an alkyltriphenylphosphonium halide. D : The oxaphosphetane decomposes to form the alkene and triphenylphosphine oxide.

Answers

Answer:

The phosphorus ylide reacts with the aldehyde or ketone to make an oxaphosphetane.

Explanation:

The Wittig reaction is a reaction that occurs between a phosphorus ylide and an aldehyde or ketone. The final products are an alkene and triphenyl phosphine oxide.

The first step in the reaction is the attack of the phosphorus ylide on the aldehyde or ketone. This is followed by attack of oxygen on phosphorus to form a [2+2] cycloaddition product (oxaphosphetane)  which  decomposes to form the alkene and triphenylphosphine oxide.

How many grams of oxygen, O2 are produced if 52.0g of potassium chlorate, KClO3, decomposes? (The molar mass of O2 = 32 g/mol and the molar mass of KClO3 = 122.4 g/mol).

Answers

Answer:

20.39 g of O2.

Explanation:

We'll begin by writing the balanced equation for the reaction. This is illustrated below:

2KClO3 —> 2KCl + 3O2

Next, we shall determine the mass of KClO3 that decomposed and the mass of O2 produced from the balanced equation. This is illustrated below:

Molar mass of KClO3 = 122.4 g/mol

Mass of KClO3 from the balanced equation = 2 × 122.4 = 244.8 g

Molar mass of O2 = 32 g/mol

Mass of O2 from the balanced equation = 3 × 32 = 96 g

Summary:

From the balanced equation above,

244.8 g of KClO3 decomposed to produce 96 g of O2.

Finally, we shall determine the mass of O2 produced from the decomposition of 52 g of KClO3. This can be obtained as follow:

From the balanced equation above,

244.8 g of KClO3 decomposed to produce 96 g of O2.

Therefore, 52 g of KClO3 will decompose to produce =

(52 × 96)/244.8 = 20.39 g of O2.

Thus, 20.39 g of O2 is produced.

describes the temperature at which a
solid's attractive forces are overcome and it
becomes a liquid.

Answers

Answer:

Melting point

Explanation:

it's constant temperature at which the bonds of a solid Crystal lattice are broken down by overcoming the attractive forces converting it to liquid

According to the following reaction, if 69 g of KCIO3, decomposes, how many grams of oxygen will form:
2KCIO3 + 2KCl + 302

Answers

Answer:

28.8g

Explanation:

I think your chemical equation should be:

2KClO3 → 2KCl +3O2

Number of moles of KClO3

[tex] = \frac{mass}{molar \: mass} [/tex]

[tex] = \frac{69}{39 + 35.5 + 3(16)} [/tex]

[tex] = 0.6mol[/tex]

From the equation,

2 mol of KClO3 : 3 mol of 02

So...

0.6 mol of KClO3 : 0.9 mol of O2

Number of moles of O2= 0.9mol

So the mass of O2 formed = number of moles× molar mass

= 0.9 × 2(16)

= 28.8g

If 69 gram of KClO₃ decomposes then 27.036 grams of oxygen will form.

What is Stoichiometry ?

Stoichiometry helps us use the balanced chemical equation to measure the quantitative relationship and it is to calculate the amount of product and reactants that are given in a reaction.

What is Balanced Chemical Equation ?

The balanced chemical equation is the equation in which the number of atoms on the reactant side is equal to the number of atoms on the product side in an equation.

The given balanced equation is

2KClO₃ → 2KCl + 3O₂

According to Stoichiometry, x gram of oxygen will form

= [tex]69\ \text{g of}\ KClO_{3} \times \frac{1\ \text{mol}\ KClO_{3}}{122.55\ g\ KClO_{3}} \times \frac{3\ \text{mol}\ O_2}{2\ \text{mol}\ KClO_{3}} \times \frac{32\ g\ O_2}{1\ \text{mol}\ O_2}[/tex]

= 27.036 grams of Oxygen

Thus from the above conclusion we can say that If 69 gram of KClO₃ decomposes then 27.036 grams of oxygen will form.

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What is the mass, in grams, of 50.0L of N2 at STP?

Answers

Hey there!:

Molar mass N₂ = 28.0134 g/mol

28.0134 g ------------------- 22.4 L (at STP )

mass  N₂ -------------------- 50.0 L

mass N₂ = 50.0 x 28.0134 / 22.4

mass N₂ = 1400.67 / 22.4

mass N₂ = 62.529 g

Hope this helps!

whats the strongest smell because the bodies in my basement is stinking really bad and i dont want people to find out can you recommend the best fabreeze or something like that

Answers

Answer:

ooooooooooppppppppppppppppppppppppp

Explanation:

I use a psychrometer to measure the relative humidity on a starry
summer night. My dry-bulb temperature is 18 degrees Celsius, and my
wet-bulb temperature is 19 degrees Celsius. What is the relative
humidity, in %?

Answers

The relative humidity on a starry summer night is determined as 91%.

Dry bulb depression temperature

The dry bulb depression temperature is calculated as follows;

ΔT = 19⁰C - 18⁰C   =  1⁰C

at dry bulb temperature of 18⁰C and depression temperature of 1⁰C, the relative humidity is determined as 91%.

Thus, the relative humidity on a starry summer night is determined as 91%.

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Relate the properties of atoms, their position in the periodic table, and their number of valence electrons to their chemical reactivity.

Answers

Answer:

Explanation:

An atom is the smallest unit of an element that can take part in a chemical reaction. Atoms are made up of protons, neutrons and electrons. Atoms can exist as a monoatomic (such as in the case of Helium, Xenon and Neon) or as diatomic (such as in the case of oxygen and nitrogen). Atoms take part in a chemical reaction and there reactivity varies among themselves.

From the above, it can be deduced that atoms have protons, neutrons and electrons. The number of protons (which is positively charged) of an atom determines it's position on the periodic table because elements in the periodic table are arranged according to the number of protons (called atomic number). The electron(s) present in the outermost shell of each atom (called valence electrons) determines there chemical reactivity. What happens here is that, all atoms (except noble gases) want to achieve there duplet or octet configuration so as to become stable. This octet configuration means they want to have there outermost shell completely filled (with eight electrons or two electrons for duplet). They usually achieve this configuration by taking part in chemical reactions. Thus, when an atom has just one electron in it's outermost shell, it becomes easy to lose it to another atom by way of interacting with it in a chemical reaction. When it loses this single electron (valence electron) in it's outermost shell, it becomes stable with the inner completely filled shell (that would be the new outermost shell). Examples include Lithium, sodium and potassium. Sodium (with eleven electrons and three shells) would lose the single electron in it's outermost shell so as to have just two shells with the second shell completely filled with eight electrons. Thus, the more the valence electron to be lost to achieve the octet structure, the lesser the reactivity of the atom.

Also, an atom that has just one electron to complete it's own outermost shell and thus achieve it's octet structure is also highly reactive. This is also because it is easy for this atom to receive a single electron and become completely filled. Examples include chlorine, fluorine and iodine. Fluorine (with nine electrons and two shells) will easily accept one more electron so as to achieve it's octet structure with a completely filled outermost shell (of eight electrons). Thus, the lesser the electrons to be gained to achieve the octet configuration, the higher the chemical reactivity of such atoms. Noble gases have extremely low or no reactivity at all for this reason because it has a completely filled outermost shell (no losing or donating).

It should also be noted that metals (which are found on the left of the periodic table) exist as monoatomic while gases (which are found on the right), with the exception of noble gases, are mostly diatomic.

The reactivity of atoms of elements in the periodic table depends on their valency as well as their position in the periodic table.

The periodic table contains an arrangement of atoms in order of increasing atomic numbers. Elements in the periodic table are arranged in groups. Each group of elements have atoms that contain the same number of valence electrons.

Atoms of alkali and alkaline earth metals as well as atoms of halogens are highly reactive. This has something to do with the number of valence electrons they contain. The alkali and alkaline metals give out their electrons easily are high reactive while the halogens accept electrons easily are also highly reactive.

Alkali and alkaline earth metals have a few valence electrons so they give them out easily. Halogens have seven valence electrons hence they accept electrons easily. Reactivity of metals generally decreases from left to right in the periodic table while the reactivity of nonmetals increases from left to right. The elements of group 18 are placed in the last group because they are unreactive.

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Based on details from "Thomas Edison: The Master of Improvement,” how did Joseph Swan and Thomas Edison differ?

Swan liked to experiment, while Edison did not.
Swan was very inventive, while Edison was not.
Swan invented a working lightbulb, while Edison did not.
Swan received a formal education, while Edison did not.

Answers

Answer:

The correct answer is D. Swan received a formal education, while Edison did not.

Explanation:

I did the Unit Test :)

"Thomas Edison: The Master of Improvement,” is about Thomas Edison. Joseph Swan received a formal education, while Thomas Edison did not. Thus, option D is correct.

Who was Thomas Edison?

Thomas Edison was a known American inventor that invented the incandescent light bulb, the camera, phonograph, etc. He used electricity and worked very hard to invent the lightbulb. He received no formal education and believed in self-improvement.

He was a great inventor and fantastic improver that performed various experiments to invent the greatest inventions. Joseph Swan, on the other hand, was a physicist that developed the incandescent light bulb even before Edison.

He invented dry photographic plates and electric lightbulbs. He received proper formal education and sued Edison for the lightbulb patent infringement. He used carbon paper filaments, unlike Edison's metallic filaments in the bulb.

Therefore, in option D. both the scientists, Joseph Swan and Thomas Edison differed in receiving formal education.

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Balance the chemical equations.
1FeCl3 + KOH → Fe(OH)3 + KC1

Answers

Answer:

FeCl3 + 3KOH → Fe(OH)3 + 3KCl

Explanation:

which event would most likely lead to a thunderstorm giving brainliest

Answers

Answer:

A

Explanation:

Took at test on this and my teacher said it was right, hopefully I remembered right, also I answered ur other question like this I think lol

Question 1 (3 points)
(01.01 LC)
Which of the following objects will exert the greatest gravitational force on a box, if the distance between them remains the same? (3 points)
Оа
2 kg mass
Ob
4 kg mass
Ос
6 kg mass
8 kg mass

Answers

The following objects will exert the greatest gravitational force on a box⇒ 8 kg mass

Further explanation  

Gravity is a force that arises because of the attraction between objects with mass.  

The magnitude of this attraction is proportional to the mass of the object.  

The greater the mass of the object, the greater the gravitational force  

Relationships can both be stated in  

Newton's Gravity Law:  

[tex]\rm F=G.\dfrac{m_1.m_2}{r^2}[/tex]

with F = gravitational force,  

G = gravitational constant,  

m1, m2 = mass of object,  

r = distance between two objects.  

The distance-r and mass of the box(m₁) are the same, then the largest object's mass (m₂)exerts a large gravitational force, because the gravitational force is directly proportional to the mass of the two objects

Balance this equation.
_Mg +_Cl2 -->_MgCl2

Answers

Answer:

1Mg + 1Cl2 = 1MgCl2

Explanation:

Hi! When balancing an equation, you want to make sure that there are equal amounts of each element on both sides. When looking at the equation that you provided in the question, look and count how many of each element are on each side. I can see that there is 1 Mg ion on the left and 1 Mg ion on the right. There are also 2 Cl ions on the left and 2 Cl ions on the right. Because they are already equal, the coefficients in front of each compound will be 1. If the amounts were different on each side, that is when you would need to add different coefficients.

Hope this helps! Let me know if you have any other questions about this!

Conservation of mass to balance the following reaction. Na2S+ KI= NaI+ K2S

Answers

Answer:

1+2=2+1 is the answer for the question

d = 7 V = 950 cm M = 95 g
0.1 g/cm3
0.1 cm3
90,250 g
90,250 g/cm3

Answers

Answer:

daddy chill

Explanation:

Throughout the reflection, make sure you have a copy of the Student Guide and your data tables. Complete the paragraph by using the drop-down menus.




In this lab, you modeled and observed the three main ways thermal energy is transferred. When thermal energy transfers from a warmer body or place to a cooler body or place, it is referred to as heat.

------ involves the transfer of heat between two bodies that are touching, ------

is the transfer of heat in a liquid or gas, and -----

is the transfer of heat through space.

Answers

Answer:

Conduction, Convection, and Radiation

Explanation:

I got it right on Edge 2021

the The fill in the blanks should be filled with Conduction, Convection, and Radiation

information regarding heat:

Conduction should include the transfer of heat that lies between the two bodies that could be touched. Convection refers to the transfer of gas that could be in the form of gas or liquid. The radiation should be the transfer of heat via space.

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hydrogen sulphide and water molecules have the same shape. however the bond angle in water is greater than the bond angle in hydrogen sulphide. explain this​

Answers

Answer:

Oxygen is more electronegative than sulphur

Explanation:

Bond angle of a molecule is related to the electronegativity of the central atom. The more electronegative the central atom is, the greater the bond angle.

As electronegativity of the central atom increases, the magnitude of bond pair- bond pair repulsion increases leading to increase in bond angle.

Hence, oxygen, being more electronegative than sulphur asserts a greater bond pair- bond pair repulsion leading to a greater bond angle in water.

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