The boiling of water is a:_______.
a. chemical change because a gas (steam) is given off.
b. chemical change because heat is needed for the process to occur.
c. physical change because the water merely disappears chemical and physical damage.
d. physical change because the gaseous water is chemically the same as the liquid.

Answer:

3) 310 g/mol

Explanation:

Hello,

In this case, for calcium carbonate, we are able to compute its gram-formula mass by considering the atomic mass of each element composing it and their subscripts as shown below:

[tex]M=3*m_{Ca}+2*m_P+4*2*m_O\\[/tex]

Thus, we compute:

[tex]M=3*40g/mol+2*31g/mol+4*2*16g/mol\\\\M=310g/mol[/tex]

Hence answer is 3) 310 g/mol . Remember this is also known as the molar mass of the mentioned compound.

Best regards.

Answer: 8 (feet)

Explanation:

24 inches = 2 feet

48 inches = 4 feet

12 inches = 1 foot

To find volume you do Base * Width * Height

2*4*1 = 8

Hope this helps!

The correct answer is  8 (feet).

How to calculate ?

Therefore, 2*4*1 = 8

learn more about capacity below,

https://brainly.com/question/15747509

#SPJ2

Answer:

409.0 kg of sodium sulfate decahydrate will produce 4.49×10⁵ kJ

of heat energy.

Explanation:

CHECK THE COMPLETE QUESTION BELOW

To make use of an ionic hydrate for storing solar energy, you place 409.0 kg of sodium sulfate decahydrate on your house roof. Assuming complete reaction and 100% efficiency of heat transfer, how much heat (in kJ) is released to your house at night? Note that sodium sulfate decahydrate will transfer 354 kJ/mol

EXPLANATION

Here we were asked to calculate the amount of heat will be generated by 409.0 kg of sodium sulfate decahydrate at night assuming there Isa complete reaction and 100% efficiency of heat transfer in the process

The molecular weight of sodium sulfate decahydrate (H₂₀Na₂O₁₄S) is needed here, so it must be firstly calculated.

The molecular weight of sodium sulfate decahydrate (H₂₀Na₂O₁₄S)

( 1*20) + (22.98*2) + (16*14)+ (32*14)= 322.186 g/mol.

Thus 409.0 kg of H₂₀Na₂O₁₄S will have a value which is equivalent to = (409000g)/(322.186 g/mol.)

=1269.453mol of H₂₀Na₂O₁₄S.

But it was stated in the the question that per mole of H₂₀Na₂O₁₄S will transfer 354 kJ heat.

Therefore, 1269.453mol will transfer 1269.453× 354 kJ = 4.49×10⁵ kJ of heat.

Hence, 409.0 kg of sodium sulfate decahydrate will produce

4.49×10⁵ kJ of heat energy.

Answer:

Approximately [tex]21\; \rm g[/tex].

Explanation:

[tex]\rm H_2SO_4[/tex] (a diprotic acid) reacts with [tex]\rm NaOH[/tex] (a monoprotic base) at a one-to-two ratio:

[tex]\rm 2\; NaOH\, (s) + H_2SO_4\, (aq) \to Na_2SO_4\; (aq) + 2\; H_2O\, (l)[/tex].

In other words, if [tex]n(\mathrm{NaOH})[/tex] and [tex]n(\mathrm{H_2SO_4})[/tex] represent the number of moles of the two compounds reacted, then:

[tex]\displaystyle \frac{n(\mathrm{H_2SO_4})}{n(\mathrm{NaOH})} = \frac{1}{2}[/tex].

Look up the relative atomic mass data on a modern periodic table:

Calculate the (molar) formula mass of [tex]\rm H_2SO_4[/tex] and [tex]\rm NaOH[/tex]:

[tex]M(\mathrm{H_2SO_4}) = 2 \times 1.008 + 32.06 + 4 \times 15.999 = 98.072\; \rm g \cdot mol^{-1}[/tex].

[tex]M(\mathrm{NaOH}) = 22.990 + 15.999 + 1.008 = 39.997\; \rm g \cdot mol^{-1}[/tex].

Calculate the number of moles of formula units in that [tex]33.8\; \rm g[/tex] of [tex]\rm NaOH[/tex]:

[tex]\begin{aligned}n(\mathrm{NaOH}) &= \frac{m(\mathrm{NaOH})}{M(\mathrm{NaOH})} \\ &= \frac{33.8\; \rm g}{39.997\; \rm g \cdot mol^{-1}} \approx 0.845\; \rm mol\end{aligned}[/tex].

Apply the ratio [tex]\displaystyle \frac{n(\mathrm{H_2SO_4})}{n(\mathrm{NaOH})} = \frac{1}{2}[/tex] to find the (maximum) number of moles of [tex]\rm H_2SO_4[/tex] that would react with the [tex]33.8\; \rm g[/tex] of [tex]\rm NaOH[/tex]:

[tex]\begin{aligned}n(\mathrm{H_2SO_4}) &= \frac{n(\mathrm{H_2SO_4})}{n(\mathrm{NaOH})} \cdot n(\mathrm{NaOH})\\ &= \frac{1}{2} \times 0.845 \approx 0.4225\; \rm mol\end{aligned}[/tex].

Calculate the mass of that [tex]0.4225\; \rm mol[/tex] of [tex]\rm H_2SO_4[/tex]:

[tex]\begin{aligned}m(\mathrm{H_2SO_4}) &= n(\mathrm{H_2SO_4}) \cdot M(\mathrm{H_2SO_4})\\ &= 0.4225 \; \rm mol \times 98.072\; \rm g \cdot mol^{-1} \approx 41.435\; \rm g \end{aligned}[/tex].

When the maximum amount of [tex]\rm H_2SO_4[/tex] is reacted, the minimum would be in excess. Hence, the minimum mass of

[tex]62\; \rm g - 41.435\; \rm g \approx 21\; \rm g[/tex] (rounded to two significant figures.)

Answer:

AT STOICHIOMETRIC POINT, THE VOLUME OF ACID ADDED IS 0.01 L

AT HALF-WAY POINT, THE VOLUME OF ACID IS 0.0050 L

Explanation:

In solving titration problems, you must remember this formula;

MaVa = MbVb

Since M a= 0.005 M

Mb = 0.010 M

Vb = 5 mL = 5 /1000 = 0.005 L

Va = unknown.

Solving for Va, we have:

Va = MbVb / Ma

Va = 0.010 * 0.005 / 0.005

Va = 0.01 L

So therefore, the volume of acid added at:

1. the stoichiometric point is 0.01 L

2. half-way point of titration is 0.01 /2 = 0.0050 L

For the pH:

Since HCl is a strong acid, it dissociate into {H30}+ ion.

First calculate the number of moles of hydronium ion

number of mole = concentration of hydronium ion {H30}+ * Volume

n = 0.005 * 0.01  = 0.00005 moles

A. At initial point of the titration, the volume of base added is 0 L

{H30]+ = n(H+)/ V = 0.00005 / 0.01 = 0.005 M

pH  = - log {0.005}

pH = 2.3

B. At the final point, since the volumes and concentrations of acid and base are the same, the pH is equal to 7.

n(H+) = n(OH^-)

pH = 7

Answer:

The excess reactant is N2H4 and the leftover mass is 10.17g.

Explanation:

Step 1:

The balanced equation for the reaction.

N2O4 + 2N2H4 —> 3N2 + 4H2O

Step 2

Determination of the masses of N2O4 and N2H4 that reacted from the balanced equation:

Molar mass of N2O4 = 92.02 g/mol

Mass of N2O4 from the balanced equation = 1 x 92.02 = 92.02g

Molar mass of N2H4 = 32.05 g/mol

Mass of N2H4 from the balanced equation = 2 x 32.05 = 64.1g

From the balanced equation above, 92.02g of N2O4 reacted with 64.1g of N2H4.

Step 3:

Determination of the excess reactant. This is illustrated below:

From the balanced equation above, 92.02g of N2O4 reacted with 64.1g of N2H4.

Therefore, 50g of N2O4 will react with = (50 x 64.1)/92.02 = 34.83g of N2H4.

From the calculations made above, we can see that only 34.83g of N2H4 reacted out of 45g that was given. Therefore, N2H4 is the excess reactant.

Step 4:

Determination of the mass of excess reactant that is leftover.

The excess reactant is N2H4 and the leftover mass can be obtained as follow:

Mass of N2H4 given = 45g

Mass of N2H4 that reacted = 34.83g

Leftover mass of N2H4 =..?

Leftover mass of N2H4 = (Mass of N2H4 given) – (Mass of N2H4 that reacted)

Leftover mass of N2H4 = 45 – 34.83

Leftover mass of N2H4 = = 10.17g.

Answer:

The functional class(es) of this compound is(are):

Explanation:

3450 cm-1 is indicative of OH stretching

1725 cm-1 is indicative of carbonyl group C=O

1100cm-1 shows carbon is bonded to electronegative element e.g C-O

Further information on molecular formula is required for proper structural elucidation

Answer:

see explanation below

Explanation:

In the first case, we have a reaction where we have the 3-chloro-3-methylpentane reacting with t-butoxide. The t-butoxide is a very voluminous base, so the strength of substracting a hydrogen atom is reduced. Therefore, the reaction taking place here will be an E2 but instead of substracting the hydrogen from the carbons 2 or 4, it will substract it from the methyl group, cause it has less steric hindrance there and the reaction will go faster.

In the second case, the sodium ethoxide is a strong base, so it will rapidly substract an atom of hydrogen from carbon 2 or 4 to form the (Z) - 3 - methyl - 2- pentene and the substitution product.

Look picture for mechanism and products.

Answer: The result section of the project contains your findings while carrying out your research or study.

Explanation:

The Results section of a research or study usually contains only the findings of your study or research.The findings which usually include

1. Data presented in tables, charts, graphs, and other figures.

2. A contextual analysis of this data explaining its meanings. Usually in sentences.

Our result gotten is not discussed in result section because every project or research work has a discussion page where every results or findings are discussed. The result section is expected to carry what you found.

Answer:

A. the law of constant composition

Explanation:

The molecules in the container would have the same composition because they would have traded around atoms until an equilibrium was reached with every molecule having 1 Hydrogen and 1 Chlorine.

Answer:

Molarity: 0.111M

% (w/w): 0.666

Explanation:

The reaction of NaOH with acetic acid (CH₃COOH) is:

NaOH + CH₃COOH → CH₃COO⁻Na⁺ + H₂O

where 1 mole of NaOH reacts per mole of acetic acid producing 1 mole of water and 1 mole of sodium acetate.

As 39.26mL ≡ 0.03926L of 0.1062M are required to titrate the solution of acetic acid. Moles are:

0.03926L × (0.1062mol / L) = 4.169x10⁻³ moles of NaOH. As 1 mole of NaOH reacts per mole of acetic acid:

4.169x10⁻³ moles of CH₃COOH.

Molarity is defined as ratio between moles of substance and volume of solution in liters. Thus, molarity of acetic acid solution is:

4.169x10⁻³ moles of CH₃COOH / 0.03754L = 0.111M

As molar mass of acetic acid is 60g/mol, 4.169x10⁻³ moles weights:

4.169x10⁻³ moles × (60g / mol) = 0.2501 g of acetic acid

Now, assuming density of solution as 1.00g/mL, 37.54mL weights 37.54g.

Thus, percent by weight is:

0.2501g CH₃COOH / 37.54g × 100 = 0.666% (w/w)

The molarity of acetic acid is 0.11M and the percent by weight is 0.666%.

Molarity of any solution is used to define their concentration and it will be calculated as:

M = n/V, where

n = moles

V = volume

Molarity of acetic acid will be calculated as:

M₁V₁ = M₂V₂, where

M₁ = molarity of acetic acid = ?

V₁ = volume of acetic acid = 37.54mL = 0.037L

M₂ = molarity of NaOH = 0.1062M

V₂ = volume of NaOH = 39.26mL = 0.039L

On putting all these values on the above equation we can calculate the molarity as:

M₁ = (0.1062)(39.26) / (37.54) = 0.11M

Now we calculate the moles of acetic acid by using the molarity formula as:

n = 0.11M × 0.037L = 0.00407 moles

Molar mass of acetic acid = 60g/mole

Mass of 0.00407 moles of acetic acid = 4.1x10⁻³ moles×(60g / mol) = 0.2501 g

Density of solution = 1.00 g/mL

So, 37.54mL in 1g/mL = 37.54g/mL

Percent by weight will be calculated as:

%w/w = 0.2501g CH₃COOH / 37.54g × 100 = 0.666% (w/w)

Hence, molarity and %(w/w) of acetic acid is 0.11M and 0.666% respectively.

To know more about percent weight, visit the below link:

https://brainly.com/question/5493941

Answer:

M=0.816M

Explanation:

Hello,

In this case, we should consider the following reaction:

[tex]AgNO_3+KCl\rightarrow KNO_3+AgCl[/tex]

Thus, by knowing the 1:1 molar ratio of silver nitrate and potassium chloride, we can easily compute the moles of silver nitrate precipitating the 1570 mg of potassium chloride considering its molar mass of 74.5513 g/mol:

[tex]n_{AgNO_3}=1570mgKCl*\frac{1gKCl}{1000mgKCl} *\frac{1molKCl}{74.5513gKCl}*\frac{1molAgNO_3}{1molKCl} \\\\n_{AgNO_3}=0.021molAgNO_3[/tex]

Then, by using the volume of silver nitrate in liters (0.0258 L), we can directly compute the molarity:

[tex]M=\frac{0.021molAgNO_3}{0.0258L}\\ \\M=0.816M[/tex]

Regards.

Answer:

Ozone has dipole moments because its molecular chemical structure is no linear.

Explanation:

This molecular form refers to the geometry of said gas, which is potentially toxic and dangerous.

This non-linear geometric shape is what makes it have dipolarity.

Answer:

Explanation:

CHECK THE ATTACHMENT FOR THE COMPLETE QUESTION AND THE DETAILED EXPLANATION

NOTE:

Equatorial atoms are referred to atoms that are attached to carbons in the cyclohexane ring which is found at the equator of the ring.

Axial atoms are atoms that exist in a bond which is parallel to the axis of the ring in cyclohexane

Answer:

All except ch4

Explanation:

NH3 N H 3 and HF can form hydrogen bonds as they have a hydrogen atom bonded to fluorine and nitrogen atoms.

Hydrogen bonds are formed between hydrogen and a highly electronegative atom such as oxygen, halogens etc.  Among the given compounds HI form hydrogen bond.

Hydrogen bond a strong bond type formed between hydrogen and an electronegative atom. Water, hydrogen halides, hydrogen sulphide etc are formed by hydrogen bonds.

Hydrogen is an electropositive atom and will easily lose an electron to a electronegative atom. Thus hydrogen bonds with atoms by sharing electrons each other where, the shared pair of electrons are attractively pulled to the electronegative atom.

Therefore, all the hydrogen bonded compounds are polar in nature.  Hydrogen bonds are strong bonds and it can be seen in proteins, DNA, and in other biomolecules.

HI or hydrogen iodide forms hydrogen bond because iodine is comparatively electronegative.

To find more on hydrogen bonds, refer here:

https://brainly.com/question/15099999

#SPJ2

Answer:I hope it will be beneficial for you

Force of attraction between the particles of solid is very strong the particles of solid are held together by strong inter molecular forces leading to the formation of a rigid structure

Force of attraction between the particles of the liquid is weak as compare to solids there particles are far away from each other and have the property to move easily.

Force of attraction between the particles of gases is very weak than the two states hence the particles of gases are highly compressible having week intermolecular interaction between them and have indefinite shape and volume

Answer:

Forces between particles in Liquids are closely packed  compared to other states of matter like the liquid and gaseous state of matter.

Explanation:

Answer:

Mass of Ga = 0.73694 gram

Explanation:

Given:

Current = 0.850 A

Time = 60 minutes

Find:

Amount of gas deposit.

Computation:

Total charge = Current × Time in second

Total charge = 0.850 × 60 × 60

Total charge = 3,060 C

Mole of electron = Total charge / Faraday constant         [Faraday constant = 96,485.3329]

Mole of electron = 3,060 / 96,485.3329

Mole of electron = 0.0317146

Moles of Ga = 1/3 [Mole of electron]

Moles of Ga = 1/3 [0.0317146]

Moles of Ga = 0.01057

Mass of Ga = molar mass × Moles of Ga

Mass of Ga = 69.72 × 0.01057

Mass of Ga = 0.73694 gram

Answer: From your question,

One could be exothermic which means that the final enthalpy will be less than the initial enthalpy. H= Hf-Hi(Hf<Hi).

In Endothermic reaction, the entropy is lowered by absorbing energy in the surronding. By so doing, the surronding losses energy and the reaction is not spontaneous.

H is positive and S (entropy) is positive.

Explanation:

Exothermic reaction is the reaction where heat is released In the surronding which lead to increase in the surronding Temperature.

Endothermic reaction is the reaction that absorb heat from the surronding and decrease the surronding Temperature.

Answer:

Gold(III) chloride

Answer:

pH = - log [concentration]

pH = - log (0.0043M)

pH = 2.37

Answer:

b) sp^2

Explanation:

Hybridization refers to the concept that atomic orbitals fuse to form newly hybridized orbitals, which in turn, influences molecular geometry and bonding properties. In chemistry, orbital hybridisation (or hybridization) is the implies the mixing of atomic orbitals to form hybrid orbitals (with different energies, shapes, etc., different from that of the component atomic orbitals) suitable for the pairing of electrons to form chemical bonds according to the principles of the valence bond theory.

In 1931 Linus Pauling proposed the idea of “mixing” the orbitals or “hybridizing” them to account for certain observed bonding patterns. Pauling proposed a sort of a combination of the orbitals giving you an orbital that has partial characters.

Hybridization is merely a mathematical construct. It is never an actual “process” that occurs within orbitals . Hybridization is a mathematical model that describes how the atomic orbitals would’ve looked like based on the observable molecular orbitals.

sp2 hybridization leads to the formation of a double bond. sigma bonds may also be formed depending on the valency of the central atom. In alkenes, an sp2 hybridized carbon atom forms a double bond in addition to two sigma bonds to other atoms.

The predicted hybridization is:

b) [tex]sp^2[/tex]

It is the integration of atomic orbitals to shape new orbitals with exclusive energies and shapes than the unique orbitals.

Given: An atom that's surrounded with the aid of using a double bond and unmarried bonds.

[tex]sp^2[/tex]  hybridization ends in the formation of a double bond. sigma bonds can also be shaped relying at the valency alkenes, an   [tex]sp^2[/tex]sigma bonds to different atoms.

Thus, correct option is b.

Find more information about Hybridization here:

brainly.com/question/26079947

Answer:

Human action has affected the population in quite a negative way. Technological innovations and urbanization gave rise to a high degree of pollution on the land, air and water.

Emission of hydrocarbons from automobiles and factories are known to pollute and cause sicknesses related to the respiratory system thereby shortening the lifespan of humans. Pollution of water bodies also cause death of sea animals and thereby reducing food availability of humans.

Answer:

[tex]M=0.0637M[/tex]

Explanation:

Hello,

In this case, the undergoing chemical reaction is:

[tex]Pb(NO_3)_2(aq)+2NaI(aq)\rightarrow PbI_2(s)+2NaNO_3(aq)[/tex]

Thus, for 0.904 g of precipitate, that is lead (II) iodide, we can compute the initial moles of lead (II) ions in lead (II) nitrate:

[tex]n_{Pb^{2+}}=0.904gPbI_2*\frac{1molPbI_2}{461gPbI_2}*\frac{1molPb(NO_3)_2}{1molPbI_2} *\frac{1molPb^{2+}}{1molPb(NO_3)_2} =1.96x10^{-3}molPb^{2+}[/tex]

Finally, the resulting molarity in 30.8 mL (0.0308 L):

[tex]M=\frac{1.96x10^{-3}molPb^{2+}}{0.0308L}\\ \\M=0.0637M[/tex]

Regards.

Answer & explanation:

Summary on electrochemical cells and redox reactions:

Electrochemical cells (or batteries) can be defined as devices capable of transforming chemical energy into electrical energy through spontaneous reactions of redox, in which electron transfer occurs.

Redox it is a chemical reaction in which there is the occurrence of oxidation and reduction of atoms of substances (chemical species) present in the process.

Oxidation is the loss of electrons by an atom of a chemical species, while reduction is the gain of electrons by an atom of a chemical species.

Thus, during an oxirreduction reaction, electrons move from the species that loses them towards the species that will receive them. This "movement" results in the formation of an electric current (or electrical energy) as occurs with batteries, for example.

Answer:

301.8 g

Explanation:

We prepare a solution with 200.4 g of water (solvent) and 101.42 g of salt (solute). The mass of the solution is equal to the sum of the mass of the solvent and the mass of the solute.

m(solution) = m(solute) + m(solvent)

m(solution) = 200.4 g + 101.42 g

m(solution) = 301.8 g (we round-off to one decimal according to the significant figures rules)

Answer:

If you're ever shaving in the bathroom, turn the water off.

Explanation:

If you do this, you can save at least 3-4 pounds of water.

Answer:

The following activities can help conserve water while taking showers:

1) Lower shower time

2) Don't leave shower running.

3) Check for leaks

Answer:

F⁻(aq) + H₂O(l) ⇄ HF(aq) + OH⁻(aq)

Explanation:

According to Brönsted-Lowry acid-base theory, an acid is a substance that donates H⁺ ions. In this sense, hydrofluoric acid is an acid according to the following equation.

HF(aq) + H₂O(l) ⇄ F⁻(aq) + H₃O⁺(aq)

According to Brönsted-Lowry acid-base theory, a base is a substance that accepts H⁺ ions. In this sense, the fluoride ion is a base according to the following equation.

F⁻(aq) + H₂O(l) ⇄ HF(aq) + OH⁻(aq)

The equilibrium constant for this reaction is Kb = 1.39 × 10⁻¹¹.

Answer:

The simplest chemical formula of the compound is Cu(C₆H₁₁O₇)₂

Explanation:

Given mass of sample = 1.4 g

mass of copper in the sample = 0.2 g

mass of the gluconate =1.4 - 0.2 = 1.2 g

The mole ratio is determined first using the formula;

mole ratio = reacting mass / atomic mass

atomic mass of copper = 63.55

mass of gluconate, C₆H₁₁O₇ = 12*6 + 1*11 + 16*7 = 195 g/mol

mole ratio ( copper : gluconate) = 0.2/63.55 : 1.4/195

mole ratio ( copper : gluconate) =  0.003 : 0.007

convert to whole number ratios by dividing with the smallest ratio

mole ratio ( copper : gluconate) = 0.003/0.003 : 0.007/0.003

mole ratio ( copper : gluconate) = 1 : 2

Therefore, the simplest chemical formula of the compound is Cu(C₆H₁₁O₇)₂