Please help me, it’s my last try

Answer:

[tex]pH = - log[H {}^{ + } ] \\ = - log(0.0000067) \\ pH = 5.17[/tex]

Answer:

if it is pure, the substances is either an element or a compound. if a substance is not chemically pure, it is either a heterogeneous mixture or a homogeneous mixture. if its composition is uniform throughout, it is a homogeneous.

Answer:

according to the path shown in the figure it will start decreasing then again it will start increasing when the path will be nearer to the star.

Reason is gravitation force is indirectly proportional to the distance.

So, option B. decrease then increase is correct

Answer:

M = 3.69 M.

Explanation:

Hello there!

In this case, according to the given information, it turns out possible for us to calculate the molar concentration of the 1.29 moles of KCl in 350 mL of solution by recalling the mathematical definition of molarity as the division of the moles by the volume in liters, in this case 0.350 L; thus, we proceed as follows:

[tex]M=\frac{1.29mol}{0.350L}\\\\M=3.69M[/tex]

Which gives molar units, M, or just mol/L.

Regards!

Answer:

B

Explanation:

AH is positive so the forward reaction is endothermic. Thus, increasing temperature would cause equilibrium to shift to the right as endothermic reaction favors higher temperature. This increases the yield of NO.

Answer:

the characteristics of ionic compounds are :

1.They form crystals.

2.They are hard and brittle.

Answer:

they form crystals.

they have high melting and boiling points.

they are hard and brittle.

they are good insulators.

when dissolve in water...they dissociate Into ions.

Answer:

D) a four-fold increase

Explanation:

According to Gay-Lussac's law, which states that the pressure of a given amount of gas is directly proportional to the temperature at a constant volume, the pressure increases with an increase in temperature.

According to this question, at a fixed volume, a four-fold increase in the temperature of a gas will lead to a four-fold increase in the pressure as well.

Answer:

Explanation:

fluorine have gained one electron that is why the sign is -1. they both have different number of protons. They have different neutron numbers. F have 10 and O have 8.

hope this helps :)

Answer: Volume occupied by 3.00 moles of oxygen gas under the same condition is 3.75 L.

Explanation:

Given: [tex]n_{1}[/tex] = 4.00 moles,          [tex]V_{1}[/tex] = 5.0 L

[tex]n_{2}[/tex] = 3.00 moles,                 [tex]V_{2}[/tex] = ?

Formula used is as follows.

[tex]\frac{V_{1}}{n_{1}} = \frac{V_{2}}{n_{2}}[/tex]

Substitute the values into above formula as follows.

[tex]\frac{V_{1}}{n_{1}} = \frac{V_{2}}{n_{2}}\\\frac{5.0 L}{4.00 mol} = \frac{V_{2}}{3.00 mol}\\V_{2} = 3.75 L[/tex]

Thus, we can conclude that volume occupied by 3.00 moles of oxygen gas under the same condition is 3.75 L.

Answer:

Q was < K. Partial pressure of hydrogen decreased, iodine increased

Explanation:

After iodine was added the Q was [Select] K so the reaction shifted toward the Products [Select] ,The partial pressure of hydrogen [Select], Iodine [Select] |,and hydrogen iodide Decreased

Based on the equilibrium:

H2(g) + I2(g) ⇄ 2HI(g)

K of equilibrium is:

K = [HI]² / [H2] [I2]

Where [] are concentrations at equilibrium

And Q is:

Q = [HI]² / [H2] [I2]

Where [] are actual concentrations of the reactants.

When the reaction is in equilibrium, K=Q.

But as [I2] is increased, Q decreases and Q was < K

The only concentration that increases is [I2], doing partial pressure of hydrogen decreased, iodine increased

Explanation:

C4H10 + 13/2O2 ---------> 4CO2 + 5H2O

so u can work out the amount of moles by doing

moles=mass/mr

mr of C4H10 is 12 × 4 + 10 =58

=7.269/58

= 0.125moles

Then u can use the molar ratio which is

6.5:4

0.125 ÷6.5 × 4 = 0.0769moles

hope this helps:)

Answer:

something that can be maintained over a period of time

Answer:

a balance between meeting today's needs.......

Explanation:

Answer:

the Molecular formula will be; C10H14O

Explanation:

Given the data in the question;

Chrysanthenone is an unsaturated ketone,

it has M+ = 150 and contains 2 double bond(s) and 2 ring(s).

molecular formula = ?

we know that ketone contain 1 oxygen and mass of oxygen is 16

so mass of the C and H remaining will be;

⇒ 150 - 16 = 134

Now we determine the number of C atoms;

⇒ 134 / 13 = 10

hydrocarbon with 10 hydrogen atom have CnH2n+2 means

⇒ ( 10 × 2 ) +2 = 22 hydrogens

But then we have 3 unsaturation meaning 6 hydrogens less and also we have ring meaning 2 more hydrogens

⇒ 22 - 6 - 2 = 14

Hence the Molecular formula will be; C10H14O

Answer:

Cuáles son las características de la luz y en qué consisten?

Explanation:

La luz es una radiación que se propaga en forma de ondas. Las ondas que se pueden propagar en el vacío se llaman ONDAS ELECTROMAGNÉTICAS. La luz es una radiación electromagnética

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

Oxygen = 45.2 Kg

Carbon = 12.6 Kg

Hydrogen = 7 Kg

Nitrogen = 2 Kg

Calcium = 1.3 Kg

Phosphorus = 0.78 Kg

Potassium = 0.25 Kg

Sulphur = 0.18 Kg

Others = 0.60 Kg

Total = 70 Kg

We can obtain the fraction of potassium of the mass of the body as follow:

Potassium = 0.25 Kg

Total = 70 Kg

Fraction of potassium = mass of potassium / Total

Fraction of potassium = 0.25 / 70

Therefore, the fraction of potassium in the body is 1/280

Learn more: https://brainly.com/question/14760859

Answer:

[tex]Key=2.5x10^{-9}[/tex]

Explanation:

Hello there!

In this case, according to the given information, it turns out possible for us to calculate the equilibrium constant value for the reverse reaction:

[tex]2CO_2(g) \rightleftharpoons 2CO(g) + O_2(g)[/tex]

By knowing that the equilibrium expression is actually:

[tex]Key =\frac{[CO]^2[O_2]}{[CO_2]^2} =\frac{1}{Keg}[/tex]

Thus, we plug in and solve for the inverse of Keq to obtain Key as follows:

[tex]Key =\frac{1}{4.0x10^{-10}}\\\\Key=2.5x10^{-9}[/tex]

Regards!

Answer:

a. Na₃PO₄

b. NH₄Cl

c. FeCl₃

d. KClO₃

Explanation:

a. Sodium tetraoxophosphate(V) Na₃PO₄

3Na⁺ + PO₄³⁻ → Na₃PO₄

b. Ammonium Chloride NH₄Cl

NH₄⁺ + Cl⁻ → NH₄Cl

c. Iron(III)chloride

Fe³⁺ + Cl⁻ → FeCl₃

d. Potassium trioxochlorate(V) KClO₃

K⁺ + ClO₃⁻ → KClO₃

Answer:

Both reactions are acid-base reactions

Explanation:

An acid base reaction is a reaction that occurs between an acid and a base. This reaction often leads to the formation of a salt in the process. The nature of the salt depends on the type of acid and base that reacted in the process.

Both HNO3 and H2SO4 are strong acids. However, ammonia is a weak base. The acid base reaction between ammonia and these strong acids is shown below;

HNO3(aq) + NH3(aq) ------>NH4NO3(aq)

H2SO4(aq) + 2NH3(aq) ----> (NH4)2SO4(aq)

Explanation:

Do đó cấu hình electron của canxi là: 1s2 2s2 2p6 3s2 3p6 4s2.

Answer:

10/3

Explanation:

Hope this helps

Answer:

The compound formula for the ammonia is

N

H

3

. It is a colorless gas. It is the result of the chemical reaction between nitrogen and hydrogen gas. The chemical reaction between the gases is shown below:

N

2

+

3

H

2

→

2

N

H

3

Answer:

The given molecules are:

CH2Br2

CH3NH2

LiF

C3H8

CF4.

Which compound consists of the hydrogen bond as the strongest intermolecular force.

Explanation:

The hydrogen bond is the electrostatic force of attraction that exists between the covalently bonded H-atom of one molecule and a high electronegative atom (N, O, F) of another molecule.

For example, H-bonding in water is represented below:

Among the given molecules,

CH2Br2 does not have H-bond because there is no either N or O or F atom in it.

In LiF also there is no H-atom and no hydrogen bond.

C3H8 also does not have H-bond in it.

CF4 also does not have H-atom or hydrogen bond in it.

The answer is CH3NH2(methylamine).

It has an intermolecular hydrogen bond in it as shown in the attachment.

The dashed line represents the H-bond.

There will be no oxygen in the product. Some of the oxygen will evaporate into the air.

Answer:

Starch.

Explanation:

When the triiodide combine with starch, it forms dark blue colour. Amylose in starch is responsible for the occurrence of a deep blue color when the iodine is combine with the starch. The iodine molecule goes inside of the amylose coil which makes a linear triiodide ion complex that goes into the coil of the starch that leads to an intense blue-black color in the end so we can say that starch turns the colour into blue.

Answer:

[tex]1.74molNO_2[/tex]

Explanation:

Hello there!

In this case, according to the given information, it turns out possible for us to perform mole-mass relationships by using the molar mass of the involved substance, in this case NO2, which is 46.0 g/mol; then we just set up a conversion factor like the one shown below:

[tex]80g*\frac{1mol}{46g}\\\\1.74molNO_2[/tex]

Regards!

Answer:

It produces free energy.

Explanation:

Photosynthesis is a process which is used by the plant for producing energy in the form of ATP. This energy is used by the plants in different activities which enables the plant to grow and develop successfully. There are some factors which causes change in the rate of photosynthesis means the production of energy for the plant body. If the environmental factors are suitable, more energy is produced through the process of photosynthesis.

Answer:

pOH = - log[OH-]

[OH-] = 0.6M

[tex]pOH \: = - log(0.6) \\ = 0.2218487496 \\ pH \: + pOH \: = 14 \\ pH \: + 0.221848749 = 14 \\ pH = 14 - 0.221848749 \\ = 13.77815125 \\ 13.8[/tex]

Answer: The number of milliliters of 654 mL for 0.587 M NaOH required to precipitate all of the [tex]Fe^{3+}[/tex] ions in 197 mL of 0.654 M [tex]FeCl_{3}[/tex] solution as [tex]Fe(OH)_{3}[/tex].

Explanation:

The reaction equation is as follows.

[tex]FeCl_{3}(aq) + 3NaOH(aq) \rightarrow Fe(OH)_{3}(s) + 3NaCl(aq)[/tex]

Therefore, moles of [tex]Fe(OH)_{3}[/tex] are calculated as follows.

Moles = Molarity of [tex]Fe(OH)_{3}[/tex]  [tex]\times[/tex] Volume (in L)

= 0.654 M [tex]\times[/tex] 0.197 L  

= 0.128 mol

Now, according to the given balanced equation 1 mole of [tex]FeCl_{3}(aq)[/tex] reacts with 3 moles of NaOH(aq). Hence, moles of [tex]Fe(OH)_{3}[/tex]  reacted are calculated as follows.

3 [tex]\times[/tex] 0.128 mol = 0.384 moles of NaOH

As moles of NaOH present are as follows.

Moles of NaOH = Molarity of NaOH [tex]\times[/tex] Volume (in L)

0.384 mol = 0.587 M [tex]\times[/tex] Volume (in L)

Volume (in L) = 0.654 L (1 L = 1000 mL) = 654 mL

Thus, we can conclude that the number of milliliters of 654 mL for 0.587 M NaOH required to precipitate all of the [tex]Fe^{3+}[/tex] ions in 197 mL of 0.654 M [tex]FeCl_{3}[/tex] solution as [tex]Fe(OH)_{3}[/tex].

Answer:

–0.13 Pa.m²

Explanation:

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

Measurement (Pa.mm²) = –1.3×10⁵ Pa.mm²

Measurement (Pa.m²) =?

We can convert from Pa.mm² to Pa.m² by doing the following:

1 Pa.mm² = 1×10¯⁶ Pa.m²

Therefore,

–1.3×10⁵ Pa.mm² = –1.3×10⁵ Pa.mm² × 1×10¯⁶ Pa.m² / 1 Pa.mm²

–1.3×10⁵ Pa.mm² = –0.13 Pa.m²

Thus, –1.3×10⁵ Pa.mm² is equivalent to –0.13 Pa.m².

The complete equation will be:

[tex](-1.3\times 10^5 Pa.mm^2)\times 10^{-6}=(-0.13) Pa.m^2[/tex]

Explanation:

Given:

The equation to convert a measurement:

[tex](-1.3\times 10^5 Pa.mm^2)\times ? = ? Pa.m^2[/tex]

To find:

The missing part of the equation.

Solution:

[tex](-1.3\times 10^5 Pa.mm^2)\times ? = ? Pa.m^2[/tex]

On LHS the unit is in [tex]Pa. mm^2[/tex] and RHS the unit is in [tex]Pa.m^2[/tex] which means that we have to convert [tex]mm^2[/tex] to [tex]m^2[/tex]

In 1 millimeter there are 0.001 meters.

[tex]1 mm = 0.001 m\\1 mm^2=0.000001 m^2=10^{-6} m^2[/tex]

So, the complete equation will be:

[tex](-1.3\times 10^5 Pa.mm^2)\times 10^{-6}=(-0.13) Pa.m^2[/tex]

Learn more about conversions here:

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Answer:

Answer: There are 1.53 moles present in   molecules of water in a beaker.

Explanation:

According to the mole concept, there are  molecules present in 1 mole of a substance.

So, number of moles present in  molecules are calculated as follows.

Thus, we can conclude that there are 1.53 moles present in   molecules of water in a beaker.

Explanation:

3

And then for Fe it should be 4 and for the products it should be 2!!