Describe the reaction of zinc with sulphuric acid​

Answer:

after the reaction between Lead (II) Nitrate solution and potassium iodide occur Lead(II) iodide  was formed and it's yellow color.

Explanation:

Pb(NO3)2 + KI = KNO3 + PbI2

Answer:

E

because it forms the ionic bond but not covalent.

The molality of a solution : 0.128 m

Given

15.9 g of Ca3(PO4)2 in 400 grams of water.

Required

The molality

Solution

molality = mol solute / kg solvent

solute= Ca3(PO4)2(MW=Molecular Weight: 310.2 g/mol)

mol solute :

[tex]\tt \dfrac{15.9}{310.2}=0.0512[/tex]

The molality :

[tex]\tt \dfrac{0.0512}{0.4~kg}=0.128~m[/tex]

Answer:

B

Explanation:

The second one is not balanced correctly.

2 NaOH + 2HNO3 → 2NaNO3 + 2 H20

I didn't notice this before but it can be balanced without the twos.

 NaOH + HNO3 → NaNO3 +  H20

It was still wrong. It needed to have the twos removed, not 2 more added. Adding two more isn't wrong, but it should be balanced without 2s if at all possible.

Answer:

the answer is D

Explanation:

i answered c and got it wrong on edg... i hope this helps :)

According to the collision theory, molecular collisions that have very specific orientations are required for a high number of effective collisions.

Collision theory is used to predict the rates of chemical reactions, particularly for gases.

Based on the collision theory, a high frequency of effective collision is dependent on the molecular collisions that have very specific orientations.

The collision theory suggests that for reactions to occur, there must collision between reacting particles.

The number of collision is dependent on the number of collision per unit time as well as fractions of effective collision.

To attain effective collision, colliding particles must be properly oriented to give the desired product.

Hence, option C is correct.

Learn more about collision theory here:

https://brainly.com/question/20628781

#SPJ2

Answer:

BIPHASIC LIQUIDS are used ear cleaning, to softening the wax so that mild infections can be treated.

Explanation:

BIPHASIC LIQUIDS are liquids that contain two immiscible phases, one is suspension and the other is emulsion. In suspension, the finely solid are dispersed in a liquid or semi solidwhich is use for medicament

The emulsion consist of immiscible liquids, one is dispersed in globules.

They are used ear cleaning, to softening the wax so that mild infections can be treated.

Answer:

Krypton (Kr)

Explanation:

Nonmetals are the elements that have opposing features and characteristics of metals. Nonmetals do not shine and are dull in appearance. They are bad conductors of heat and electricity. They are brittle and cannot be beaten into sheets. The density, melting and boiling points of the nonmetals are low. Krypton (Kr) is a non metal whose atomic number is 36.

Answer:

Electron pair geometry- trigonal planar

There is one lone pair around the boron atom

The geometry of BH2 is bent

Explanation:

The valence shell electron pair repulsion theory offers a frame work for determining the shape of molecules based on the number of electron pairs of the valence shell of the central atom in the molecule.

In BH2-, the central atom is boron. There is a lone pair on boron. Owing to the lone pair on boron, the molecular geometry of BH2 is bent.

The geometry of the electron pair around the Boron atom in [tex]BH_2[/tex] is called the trigonal planar. In this case, there is a pair of isolated electrons around Boron, which is the central atom, allowing the [tex]BH2[/tex] molecule to have a folded geometry.

We can arrive at this answer because:

This allows for a folded geometry around the molecule, allowing Boron to be an exception to the octet rule and achieve stability with 5 electrons in the valence layer.

More information:

https://brainly.com/question/22403376?referrer=searchResults

Answer:

a. pentane = C5H12

b. Heptane = C7H16

c. Hexyne = C6H10

d. Octene = C8H16

e. Nonane = C9H20

Hope it helps.

1-pentene

Molecular Formula C5H10

Condensed Structural FormulaCH2=CH(CH2)2CH3

Melting Point (°C)–138

Boiling Point (°C)30

2- heptane is the straight-chain alkane with the chemical formula H3C(CH2)5CH3 or C7H16, and is one of the main components of gasoline (petrol).

Answer: (a) [tex]\Delta S^{0}[/tex] = - 242.2J/K.mol

              (b) [tex]\Delta S^{0}[/tex] = 163.34J/K.mol

              (c) Yes

Explanation: Entropy is the measure of randomness or disorder of a system. Standard Entropy has the symbol [tex]S^{0}[/tex].

Mathematically, Entropy is defined as

[tex]\Delta S^{0}=\Sigma S^{0}(products)-\Sigma S^{0}(reagents)[/tex]

Each substance has its own entropy value.

(a) Combustion of Methane:

[tex]CH_{4}+2O_{2}[/tex] ⇒ [tex]CO_{2}+2H_{2}O[/tex]

Using standard entropy table, entropy will be:

[tex]\Sigma S^{0}(products)=214+2(69.91)[/tex] = 353.8

[tex]\Sigma S^{0}=186.264+2(205.138)[/tex] = 596.54

[tex]\Delta S^{0}=[/tex] 353.8 - 596.54

[tex]\Delta S^{0}=[/tex] - 242.2

Standard Entropy for combustion of methane is [tex]\Delta S^{0}=[/tex] - 242.2 J/K.mol.

(b) Hydrolysis of Water:

[tex]H_{2}O_{(l)}[/tex] ⇒ [tex]H_{2}_{(g)}+1/2O_{2}_{(g)}[/tex]

[tex]\Sigma S^{0}(products)=130.684+0.5(205.138)[/tex] = 233.253

[tex]\Sigma S^{0}(reagents)=69.91[/tex]

[tex]\Delta S^{0}=[/tex] 233.253 - 69.91

[tex]\Delta S^{0}=[/tex] +163.34

Standard Entropy for hydrolysis of water is [tex]\Delta S^{0}=[/tex] + 163.34 J/K.mol

(c) Yes, the results prove the general rule: Reactions Entropies are positive for net formation of gas and negative for net reduction of gas. This happens because, as entropy is the measure of disorder, the entropy for gases are greater than for liquids and solids. So, when there is formation of a gas, Entropy increases and when there isn't, entropy decreases.

Answer: 2

Explanation:

A combustion reaction must include O2 as a reactant.

An inorganic substance almost never includes carbon.

So, by process of elimination:

1. Carbon is a reactant = probably not

2. Has O2, no carbon = yes

3. O2 is not a reactant = no

4. Carbon is a reactant = probably not

An example of the combustion of an inorganic substance is:

2 Ca + O₂ ⇒ 2 CaO

We have 4 reactions and we want to determine which is an example of combustion of an inorganic substance.

A combustion reaction is a reaction in which a substance reacts with oxygen gas, releasing energy in the form of light and heat.

Organic substances always contain carbon while most inorganic substances do not contain carbon.

Let's consider the following reactions.

This is a combustion reaction but C₃H₈ is an organic substance.

This is an example of the combustion of an inorganic substance.

This is not a combustion reaction.

This is a combustion reaction but CH₃COOH is an organic substance.

An example of the combustion of an inorganic substance is:

2 Ca + O₂ ⇒ 2 CaO

Learn more about combustion here: https://brainly.com/question/4155165

Answer:

a. volcanic changes create new land

Answer: B

We use stoichiometric amounts of P4 and PH3

NO.9) It's actual yield

Answer:

hexane C6H14

IS YOUR ANSWER

Explanation:

I HOPE IT HELPS MATE

MARK ME BRAINLIEST PLS

I WILL ALWAYS HELP YOU UNDERSTANDING YOUR ASSINGMENTS

HAVE A GREAT DAY

#CAPTAINPOWER :)

The ratio of concentration of ammonia and ammonium chloride : 0.05

Given

pOH=5

Kb for NH3 =1.8 x 10-4

Required

The ratio of concentration of ammonia (NH₃) and ammonium chloride(NH₄Cl)

Solution

Solutions containing ammonia and its salt: ammonium chloride are called alkaline buffers

Can be formulated : ( for the same of the volume, mol=concentration)

[tex]\tt \displaystyle [OH-]=Kb\times\frac{weak\:base\:mole}{salt\:mole\times valence}[/tex]

pOH=-log [OH⁻]

pOH=5⇒[OH⁻]=10⁻⁵

Valence for NH₄Cl = 1, so the concentration ratio :

[tex]\tt 10^{-5}=1.8\times 10^{-4}\times \dfrac{[~NH_3]}{[NH_4Cl]}\\\\0.05=\dfrac{[~NH_3]}{[NH_4Cl]}[/tex]

Answer:

It would be working properly and providing her energy for her daily activities.

Explanation:

Hello!

In this case, since her oxygen is actually working properly, it is going to be travelling throughout her entire body (via blood) and therefore carbon dioxide would be released as the exhalation product due to cellular respiration carried out in the alveoli which provides energy for her daily activities.

However, the intrusion of different molecules to oxygen into her cells may affect the rate at which cellular respiration is carried out and therefore she may feel tired because such process provides energy to the body.

Best regards!

Answer:

Radiation

Explanation:

Sun rays shine on earth. Thats radiation.

The complete question is attached to this answer

Answer:

2.75 * 10^-5 m

Explanation:

The energy of the absorbed photon = ΔE

ΔE = - Ry (1/n^2 final - 1/n^2initial)

Given that Ry = 2.18 *10^-18 J

nfinal = 9

ninitial =8

ΔE = - 2.18 *10^-18 (1/9^2- 1/8^2)

ΔE = - 2.18 *10^-18 (0.0123 - 0.0156)

ΔE = 7.194 * 10^-21 J

But

ΔE =hc/λ

h = 6.6 *10^-34Js

c= 3 * 10^8 ms-1

λ= the unknown

λ= hc/ΔE

λ= 6.6 *10^-34 * 3 * 10^8/ 7.194 * 10^-21

λ= 2.75 * 10^-5 m

Answer:

Im pretty sure its hydrocarbon

Explanation:

Answer:

[tex]U_2=48.3kJ[/tex]

Explanation:

Hello!

In this case, since the fist law of thermodynamics helps us to understand how the change in internal energy is defined in terms of the head added to the system and the work done by the system:

[tex]Q+W=\Delta U[/tex]

In such a way, since 8.3 kJ of heat are absorbed by the system, 3.5 kJ are done by the system and the initial internal energy is 43.5 kJ, the final internal energy turns out:

[tex]U_2=U_1+Q-W\\\\U_2=43.5kJ+8.3kJ+3.5kJ\\\\U_2=48.3kJ[/tex]

Best regards!

It's answer is c. N2

The maximum bond energy is of N2 because N2 molecule is formed by 3 covalent bonds and O2 molecule is formed by 2 covalent bonds.

Hope it helps :)

Answer:

help you with what?

Explanation:

Answer:

A

Explanation:

I took a test like this and my teacher said this was right so ye. hopefully I remembered correctly if its wrong im sorry ;C

Answer: A

Explanation: A thunderstorm forms when warm, moist air rises into cold air. Hope this helps. :)

Answer:

See explanation

Explanation:

Now taking A, we can see that if we double the amount of A while keeping the amount of B constant, the rate of reaction doubles, hence we can write;

2^n = 2^1

hence n =1

For B, when the amount of B is doubled while keeping the amount of A constant, the rate of reaction increases eight times. Hence we can write;

2^n = 8

2^n = 2^3

n=3

Hence this reaction has an overall order of 1 + 3 = 4

So we can write;

rate =k[A] [B]^3

Answer:

i do believe it is C. Chemical energy in food is transformed into mechanical energy as our body rides a bicycle down the street. but if i am wrong plz don't come at me but i believe that is right

Explanation:

Answer:

i do believe it is C. Chemical energy in food is transformed into mechanical energy as our body rides a bicycle down the street. but if i am wrong plz don't come at me but i believe that is right

Explanation:

Answer:

-189.55°C

Explanation:

Given data:

Initial volume of gas = 3.6 L

Final volume of gas = 15.5 L

Initial temperature = ?

Final temperature = 87°C (87+273 = 360 K)

Solution:

The given problem will be solve through the Charles Law.

According to this law, The volume of given amount of a gas is directly proportional to its temperature at constant number of moles and pressure.

Mathematical expression:

V₁/T₁ = V₂/T₂

V₁ = Initial volume

T₁ = Initial temperature

V₂ = Final volume  

T₂ = Final temperature

Now we will put the values in formula.

V₁/T₁ = V₂/T₂

T₁  = V₁T₂  /V₂

T₁   = 3.6 L × 360 K / 15.5 L

T₁   = 1296 L.K / 15.5 L

T₁  = 83.6 K

Kelvin to °C:

83.6 K - 273.15 = -189.55°C

Answer:When a single compound breaks down into two or more compounds or elements in a chemical reaction then it is known as decomposition reaction.

The chemical symbol for sodium carbonate is .

The decomposition of sodium carbonate is:

The decomposition of sodium bicarbonate,  will result in the formation of sodium oxide,  and carbon dioxide, .

Hence, carbon dioxide,  will produce with sodium oxide,  on decomposition of .

Explanation:Na2CO3 Na2O +CO2   CO2 is the answer

Answer:

Explanation:

proposed an early model of the atom as a central nucleus containing protons and neutrons being orbited by electrons in shells. As previously discussed, there is a connection between the number of protons in an element, the atomic number that distinguishes one element from another, and the number of electrons it has. In all electrically-neutral atoms, the number of electrons is the same as the number of protons. Each element, when electrically neutral, has a number of electrons equal to its atomic number.

Answer:

You can check diagram with number of proton neutron and electrons

Explanation:

Answer:

0.75 mol

Explanation:

Given data:

Number of moles of Na = 0.75 mol

Mass of water = 500 g

Moles of hydrogen gas produced = ?

Solution:

Chemical equation:

Na + H₂O   →      NaO + H₂

Number of moles of water:

Number of moles = mass/molar mass

Number of moles = 500 g/ 18 g/mol

Number of moles = 27.8 mol

now we will compare the moles of hydrogen gas with both reactant.

                   Na         :          H₂

                    1            :          1

                  0.75       :         0.75

                 H₂O        :          H₂

                   1            :           1

               27.8          :         27.8

sodium will act as limiting reactant it produced small number of moles of hydrogen gas as compared to water.

Thus, number of moles of hydrogen gas are 0.75 mol.