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The presence of a non-volatile salt will decrease the freezing point of water and this process is called depression in freezing point. Thus option D is correct.

Freezing point of a substance is the temperature at which it converts from its liquid state to solid state where, both the states are in equilibrium. Freezing point of water is zero degree celsius.

The freezing point of a solvent depends on some parameters such as the bond type, molecular weight, temperature, pressure etc.

When a non-volatile solute is added to the solvent its freezing point decreases from its initial value. Because presence of non-volatile salts will affect the intermolecular attraction and thereby the energy that must be applied to freeze the compound.

Therefore, the freezing point of water decreases, when sodium chloride is added into it. Thus option D is correct.

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Answer:

Ne 20: 10

and

Ne 22: 12

Explanation:

Ne-20:

N = A - Z = 20 - 10 = 10 neutrons

Ne-22:

N = A - Z = 22 - 10 = 12 neutrons

N: number of neutrons

A: mass number

Z: atomic number

Answer:

[tex]T_2=400.73K[/tex]

Explanation:

From the question we are told that:

Activation energy [tex]E_a= 51.02 kJ/mol.=>51.02*10^3J/mol[/tex]

Reaction Ratio [tex]\triangle K=4.50[/tex]

Initial Temperature [tex]T_1=365K[/tex]

Generally the equation for Final Temperature [tex]T_2[/tex] is mathematically given by

 [tex]log \triangle K=\frac{E_a}{2.303R}*(\frac{T_2-T_1}{T_1T_2})[/tex]

Where

 [tex]R=Gas constant[/tex]

 [tex]R =8.3143[/tex]

Therefore

 [tex]log 4.50=\frac{51.2*10^3}{2.303*8.31432}*(\frac{T_2-365}{365*T_2})[/tex]

 [tex]log 4.50=7.328*\frac{T_2-365}{T_2}[/tex]

 [tex]0.0892=\frac{T_2-365}{T_2}[/tex]

 [tex]0.0892T_2=T_2-365[/tex]

 [tex]365=T_2-0.0892T_2[/tex]

 [tex]365=0.91T_2[/tex]

 [tex]T_2=\frac{365}{0.91}[/tex]

 [tex]T_2=400.73K[/tex]

Answer:

C

Explanation:

increasing the temperature will favour the forward reaction therefore the reaction system will try to counteract that by producing more heat and NO2 therefore increases the amount of products produced

increasing the pressure will favour the forward reaction as it has more moles of substance therefore if the forward reaction is favored, more product will be produced

Answer:

C.) lV and V

Explanation:

I got it correct on founders edtell

Answer: 2.20 g Pb

They gave us the masses of two reactants and asked us to determine the mass of the product. We will need a chemical equation with masses and molar masses, so, let's gather all the information in one place.

Mᵣ:       239.27   32.00        207.2

           2PbS   +   3O₂   ⟶  2Pb   +   2SO₃

m/g:      2.54        1.88

Molar concentration is a measure of the concentration of a chemical species, in particular of a solute in a solution, in terms of amount of substance per unit volume of solution.

Answer:

Meaning, Advantages & Disadvantages of - Osmosis, Multiflash Distillatiob

Explanation:

Advantages - It assists equalising concentration of solute on two sides of membrane. Reverse Osmosis is used for efficient water softening, it is easy to maintain.

Disadvantages - It needs a lot of energy. A lot of pressure is required for deionisation. Water acidity level increases, as minerals get deionised.

Advantages - Its Cost efficient , distillation uses waste heat. It has High gain output ratio. Quality of feedwater is less significant, compared to reverse osmosis.

Disadvantages - It has high operating cost in case of waste heat unavailability. High temperature imply high corrosion & scale formation.

Explanation:

2x²=8

x²=8/2

x=√4

x=2

hope it helps.

Answer:

[tex]\huge \fbox \pink {A}\huge \fbox \green {n}\huge \fbox \blue {s}\huge \fbox \red {w}\huge \fbox \purple {e}\huge \fbox \orange {r}[/tex]

[tex] {2x}^{2} = 8 \\ {x}^{2} = \frac{8}{2} \\ {x}^{2} = 4 \\ x = \sqrt{4} \\ x = 2[/tex]

ʰᵒᵖᵉ ⁱᵗ ʰᵉˡᵖˢ

[tex] \huge\purple{ \mid{ \underline{ \overline{ \tt ꧁❣ ʀᴀɪɴʙᴏᴡˢᵃˡᵗ2²2² ࿐ }} \mid}}[/tex]

Answer:

Wind energy

Explanation:

An ideal source of energy needs to be reliable, cost effective, safe and must lead to almost zero adverse environmental impact.

Wind energy is energy obtained from air moving at high velocity. This energy is harvested using windmills which convert mechanical energy to electrical energy.

Wind is inexpensive because it occurs naturally. However, a large expanse of land is required in order to mount sufficient number of windmills that will generate enough electrical energy for practical purposes.

This method of electricity generation is safe and does not lead to any environmental hazard unlike the burning of fossil fuels, use of nuclear energy or loss of habitat due to hydroelectric power generation.

[tex]1) \: decomposition[/tex]

[tex]2) \:hydrocarbon \: combustion[/tex]

[tex]3) \: formation[/tex]

[tex]4) \: double - replacement[/tex]

[tex]5 \: double - replacement[/tex]

[tex]6) \: formation[/tex]

[tex]7)double \: - replacement[/tex]

[tex]8) \: double - replacement[/tex]

Answer:

2-pentanone.

Explanation:

Hello there!

In this case, for the given compound and, in agreement with the octet rule, it is possible to realize that the CO is actually C=O as shown below:

CH3  -  C  -  CH2  -  CH2  -  CH3

            ||

           O

Thus, since the C=O stands for the carbonyl group within the parent chain, we infer this is a ketone and more specifically 2-pentanone as it has five carbon atoms.

Regards!

Answer:

9 moles of NaNO3 is obtained

Explanation:

The balanced chemical reaction equation for the reaction is;

Al(NO3)3 + 3NaCl-------> 3NaNO3 + AlCl3

Now, we have to determine the limiting reactant. The limiting reactant yields the least amount of NaNO3.

1 mole of Al(NO3)3 yields 3 moles of NaNO3

4 moles of Al(NO3)3 yields 4 * 3/1 = 12 moles of NaNO3

Also,

3 moles of NaCl yields 3 moles of NaNO3

9 moles of NaCl yields 9 * 3/3 = 9 moles of NaNO3

Hence, NaCl  is the limiting reactant and 9 moles of NaNO3 is obtained.

9 moles of NaNO₃ is obtained.

[tex]Al(NO_3)_3 + 3NaCl-----> 3NaNO_3 + AlCl_3[/tex]

From the reaction, it is seen that the limiting reactant yields the least amount of NaNO₃.

1 mole of Al(NO₃)₃ yields 3 moles of NaNO₃

4 moles of Al(NO₃)₃ yields 4 * 3/1 = 12 moles of NaNO₃

Also,

3 moles of NaCl yields 3 moles of NaNO₃

9 moles of NaCl yields 9 * 3/3 = 9 moles of NaNO₃

Hence, NaCl  is the limiting reactant and 9 moles of NaNO₃ is obtained.

Find more information about Balanced chemical reaction here:

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Answer:

[tex]V_2=27.87L[/tex]

Explanation:

Hello there!

In this case, according to the given information, it turns out possible for us to solve this problem by using the Charles' law a directly proportional relationship to understand the volume-temperature behavior:

[tex]\frac{V_2}{T_2} =\frac{V_1}{T_1}[/tex]

Thus, we solve for the final volume, V2, and make sure the temperature are in Kelvin as shown below:

[tex]V_2 =\frac{V_1T_2}{T_1} \\\\V_2=\frac{26.42L(92+273.15)K}{(73+273.15)K} \\\\V_2=27.87L[/tex]

Regards!

Answer:

The answer is B

Brainliest please!

Answer:

Animals are used in scientific research to help us understand our own bodies and how they work. This is necessary to develop new medicines. Animals are also used to safety test potential medicines before they are tested in people and to check the safety of other chemicals.

Explanation:

Answer:

2.35x10²³ molecules of C2Cl4 are present

Explanation:

To solve this question we must convert, as first, the mass of C2Cl4 to moles using its molar mass (C2Cl4 = 165.83g/mol). Then, using Avogadro's number we can find the number of molecules:

Moles C2Cl4:

73.1g * (1mol / 165.83g) = 0.441 moles C2Cl4

Molecules:

0.441 moles C2Cl4 * (6.022x10²³molecules / 1mol) =

Answer:

6

Explanation:

lol

Answer:

What is

the volume of the balloon when the temperature is 310K?

Answer:the final mass of copper is  3.84 g. There was an increase in mass of 1.84 g from the initial mass of 2.0 g.

Explanation:

Well arranged question is;

Select the statement that is FALSE about this experiment. Group of answer choices;

A) Changing metal solution will affect the redox potential.

B) To ensure consistent data, collect the redox potential values at least three times.

C) Changing temperature will affect the redox potential.

D) To ensure stable reading, insert the conductivity meter in the solution for at least 60 seconds.

E) Changing concentration will affect the redox potential.

Answer:

D) To ensure stable reading, insert the conductivity meter in the solution for at least 60 seconds.

Explanation:

Usually, redox potential is the measure of the ability of chemical elements to gain/lose electrons from/to an electrode respectively and after which they undergo reduction or oxidation respectively.

From online sources on experiments to determine redox potential, and taking into account the nernst equation which is; E_cell = E_0 – (RT/nF)•ln Q

Where;

E_cell is cell potential

E_0 is potential of the cell under standard conditions

R is universal gas constant

T is temperature

n is the number of electrons that are transferred in the redox reaction

F is Faraday's constant

Q is reaction quotient

Now, with all that in mind and looking at the options, the one that is false is option D.

Answer:

The answer is "2%"

Explanation:

Equation:

[tex]HNO_2\ (aq) \leftrightharpoons H^{+} \ (aq) + NO_2^{-}\ (aq) \\\\\ K_a = 4.0\times \ 10^{-4}[/tex]

[tex]H^{+}=?[/tex]

Formula:

[tex]Ka = \frac{[H^{+}][NO_2^{-}]}{[HNO_2]}[/tex]

Let

[tex][H^{+}] = [NO_2^{-}] = x[/tex] at equilibrium

[tex]x^2 = (4.0\times 10^{-4})\times 1.0\\\\x = ((4.0\times 10^{-4})\times 1.0)^{0.5} = 2.0 \times 10^{-2} \ M\\\\[/tex]

therefore,

[tex][H^{+}] = 2.0\times 10^{-2} \ M = 0.02 \ M[/tex]

Calculating the % ionization:

[tex]= \frac{([H^{+}]}{[HNO_2])} \times 100 \\\\= \frac{0.02}{1}\times 100 \\\\= 2\%\\\\[/tex]

The approximate percent ionization of HNO₂ in a 1.0 M HNO₂ (aq) solution is 2%.

% ionization of any compound will be calculated as follow:

% ionization = ([ion]/[acid or base]) ₓ 100

Given chemical reaction with ICE table will be represented as:

                           HNO₂(aq) → H⁺(aq) + NO₂⁻(aq)

initial                          1                0             0

change                      -x               +x           +x

equilibrium              1-x                x             x

Equilibrium constant will be represented as:
Ka = [H⁺][NO₂⁻] / [HNO₂]

Acid dissociation constant for HNO₂ = 4×10⁻⁴

Putting all values in the above equation, we get

4×10⁻⁴ = x² / 1-x

Value of changeable quantity is very less, so we neglect from the concentration of HNO₂.

4×10⁻⁴ = x²

x = 2 × 10⁻²

So, the concentration of H⁺ ion = 2 × 10⁻²M

Now we put all these values in the % ionization equation, we get

% ionization = (0.02/1) × 100 = 2%

Hence , % ionization is 2%.

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Answer:

Amount of iron fillings in mixture = 60 mg

Explanation:

Given:

Total mass of mixture = 100 mg

Amount of salt in mixture = 10 mg

Amount of sand in mixture = 30 mg

Find:

Amount of iron fillings in mixture

Computation:

Using Law of Conservation of mass;

Total mass of mixture = Amount of salt in mixture + Amount of sand in mixture + Amount of iron fillings in mixture

100 = 10 + 30 + Amount of iron fillings in mixture

100 = 40 + Amount of iron fillings in mixture

Amount of iron fillings in mixture = 100 - 40

Amount of iron fillings in mixture = 60 mg

Answer:

Start your streak by answering any question. You'll get bonus points from day 2.

Answer:

0.0123 mol

Explanation:

Step 1: Convert 34.0 °C to Kelvin

We will use the following expression.

K = °C + 273.15 = 34.0 + 273.15 = 307.2 K

Step 2: Convert 148 cm³ to L

We will use the conversion factors:

[tex]148cm^{3} \times \frac{1mL}{1cm^{3}} \times \frac{1L}{1000mL} = 0.148L[/tex]

Step 3: Convert 212 kPa to atm

We will use the conversion factor 1 atm = 101.325 kPa.

212 kPa × 1 atm / 101.325 kPa = 2.09 atm

Step 4: Calculate the moles of nitrogen gas

We will use the ideal gas equation.

P × V = n × R × T

n = P × V / R × T

n = 2.09 atm × 0.148 L / (0.0821 atm.L/mol.K) × 307.2 K = 0.0123 mol

Answer:

B. The mass is greater after the reaction because the number of

atoms increases.

V = 3.9 L

Explanation:

Given:

T = 23°C + 273 = 296K

n = 0.16 mol He

P = 101 kPa = 0.997 atm

R = universal gas constant = 0.08205 L-atm/mol-K

V = ?

Using the ideal gas law,

PV = nRT

V = nRT/P

= (0.16 mil He)(0.08205 L-atm/mol-K)(296K)/(0.997 atm)

= 3.9 L

Answer:

A. As pressure decreases, the concentration of gas molecules in the solution increases.

D. The solubility of nitrogen gas at 2.00 atm is twice the solubility of the gas at 1.00 atm.

F. More gas molecules are soluble as pressure is increased.

The solubility is 188.3 mg of N2 gas/100 g water.

Explanation:

As the pressure on the gas decreases, the volume of gas molecules in the solution increases due to having distance from each other. The solubility of nitrogen gas at 2.00 atm is twice the solubility of the gas at 1.00 atm because there is more pressure on the gas molecules so due to more compression, the gas becomes more soluble. More gas molecules are soluble as pressure is increased. The solubility is 188.3 mg of N2 gas/100 g water if the atmospheric pressure is increases from 3.08 atm to 8.00 atm. This value is calculated with the help of formula i.e. P2/P1 = S2/S1.