Which of the following choices is a source of groundwater pollution?
O sewage
very warm water
O silt
O All of these choices are correct.

Answer:

See explanation

Explanation:

The molecular equation is depicted below;

The balanced molecular reaction equation is;

2 NaCl (aq) + 2 H2O (l) → 2 NaOH (aq) + Cl2 (g) + H2 (g)

The complete ionic equation is;

2Na^+(aq) + 2Cl^-(aq) + 2H2O(l) ---> 2Na^+(aq) + 2OH^-(aq) + Cl2(g) + H2(g)

Hence, net Ionic equation;

2Cl^-(aq) + 2H2O(l) ---> 2OH^-(aq) + Cl2(g) + H2(g)

Answer:

Because of its weak intermolecular forces.

Explanation:

Hello there!

In this case, according to the given description, it turns out possible for us to recall the chemical structures of both ethanol and dimethyl ether as follows:

[tex]CH_3CH_2OH\\\\CH_3COCH_3[/tex]

Thus, we can see that ethanol have London dispersion forces (C-C bonds), dipole-dipole forces (C-O bonds) and also hydrogen bonds (O-H bonds) which make ethanol a liquid due to the strong hydrogen bonds. On the other hand, we can see that dimethyl ether has just London and dipole forces, which are by far weaker than hydrogen bonding, that makes it unstable when liquid and therefore it tends to vaporize quite readily.

Regards!

Answer:

It is D).cyclohexanone ( in acellus)

Explanation:

Answer:

A chemistry student must write down in her lab notebook the concentration of a solution of sodium thiosulfate. The concentration of a solution equals the mass of what's dissolved divided by the total volume of the solution.

Explanation:

The concentration of a solution can be measured in terms of molarity.

The molarity of a solution can be defined as the number of moles of solute present in the total volume of the solution.

The number of moles of solute is the ratio of mass of solute to molar mass of solute.

Hence,

[tex]Molarity=\frac{mass of solute}{molar mass of solute} * \frac{1}{volume of solution in L.}[/tex]

Answer: The empirical and molecular formula for the given organic compound is [tex]C_9H_{13}O_3N[/tex]

Explanation:

Let the mass of the compound be 100 g

Given values:

% of C = 59.0%

% of H = 7.15%

% of O = 26.20%

% of N = 7.65%

Mass of C = 59.0 g

Mass of H = 7.15 g

Mass of O = 26.20 g

Mass of N = 7.65 g

The number of moles is defined as the ratio of the mass of a substance to its molar mass. The equation used is:

[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex] ......(1)

To formulate the empirical formula, we need to follow some steps:

Molar mass of C = 12 g/mol

Molar mass of H = 1 g/mol

Molar mass of O = 16 g/mol

Molar mass of N = 14 g/mol

Putting values in equation 1, we get:

[tex]\text{Moles of C}=\frac{59.0g}{12g/mol}=4.917 mol[/tex]

[tex]\text{Moles of H}=\frac{7.15g}{1g/mol}=7.15 mol[/tex]

[tex]\text{Moles of O}=\frac{26.20g}{16g/mol}=1.6375 mol[/tex]

[tex]\text{Moles of N}=\frac{7.65g}{14g/mol}=0.546 mol[/tex]

Calculating the mole fraction of each element by dividing the calculated moles by the least calculated number of moles that is 0.546 moles

[tex]\text{Mole fraction of C}=\frac{4.917}{0.546 }=9[/tex]

[tex]\text{Mole fraction of H}=\frac{7.15}{0.546 }=13[/tex]

[tex]\text{Mole fraction of O}=\frac{1.6375}{0.546 }=2.99\approx 3[/tex]

[tex]\text{Mole fraction of N}=\frac{0.546}{0.546 }=1[/tex]

The ratio of C : H : O : N = 9 : 13 : 3 : 1

The empirical formula of the compound becomes [tex]C_9H_{13}O_3N_1=C_9H_{13}O_3N[/tex]

To calculate the molecular formula, the number of atoms of the empirical formula is multiplied by a factor known as valency that is represented by the symbol, 'n'.

[tex]n =\frac{\text{Molecular mass}}{\text{Empirical mass}}[/tex] .....(2)

We are given:

Mass of molecular formula = 183 g/mol

Mass of empirical formula = 183 g/mol

Putting values in equation 2, we get:

[tex]n=\frac{183g/mol}{183g/mol}=1[/tex]

Multiplying this valency by the subscript of every element of empirical formula, we get:

[tex]C_{1\times 9}H_{1\times 13}O_{1\times 3}N_{1\times 1}=C_9H_{13}O_3N[/tex]

Hence, the empirical and molecular formula for the given organic compound is [tex]C_9H_{13}O_3N[/tex]

Answer:

Option A. 11

Explanation:

We'll begin by calculating the concentration of Hydroxide ion in the solution. This can be obtained as follow:

KOH (aq) —> K⁺(aq) + OH¯(aq)

From the balanced equation above,

1 mole of KOH produced 1 mole of OH¯.

Therefore, 1×10¯³ M KOH will also produce 1×10¯³ M OH¯.

Next, we shall determine the pOH of the solution. This can be obtained as follow:

Concentration of Hydroxide ion [OH¯] = 1×10¯³ M

pOH =?

pOH = –Log [OH¯]

pOH = –Log 1×10¯³

pOH = 3

Finally, we shall determine the pH of the solution. This can be obtained as follow:

pOH = 3

pH =?

pH + pOH = 14

pH + 3 = 14

Collect like terms

pH = 14 – 3

pH = 11

Therefore, the pH of the solution is 11

Answer:

Neutron has no charge while electron has a negative charge and proton has a positive charge

Answer:

Empirical formula has a molar mass of 30.01g/mol and molecular formula is C₆H₁₂O₆

Explanation:

Molar mass of a molecule is the sum of the molar mass of each atom. In CH2O we have:

1C = 1*12.01g/mol = 12.01g/mol

2H = 2*1g/mol = 2g/mol

1O = 1*16g/mol = 16g/mol

Empirical formula of CH2O is:

12.01g/mol + 2g/mol + 16g/mol = 30.01g/mol

As the molecular compound has a molar mass of 180.0g/mol the molecular formula is:

180.0g/mol / 30.01g/mol = 6 times the empirical formula. That is:

Answer:

1.75L

Explanation:

Reaction of decomposition is:

2KClO₃(s) →  2KCl(s) + 3O₂(g)

We determine moles of salt:

4.35 g . 1 mol /122.55 g = 0.0355 moles

Ratio is 2:3. 2 moles of salt can produce 3 moles of oxygen

Then, our 0.0355 moles of chlorate may produce (0.0355 . 3)/ 2 = 0.0532 moles.

We have determined, moles of gas and we have data of pressure and temperature. To find out the volume, we apply the Ideal Gases Law:

We convert T° from °C to K → 27°C + 273 = 300K

P . V = n . R . T

0.75 atm . V = 0.0532 mol . 0.0821 L.atm/mol.K . 300K

V = (0.0532 mol  . 0.0821 L.atm/mol.K . 300K) / 0.75 atm

V  = 1.75 Liters

Answer:

The tasks which form the preliminaries to a descriptive investigation are: Making careful objective observations. Asking the relevant scientific questions.

Answer:

compressable

Explanation:

as liquid nitrogen came out from container the force exerted on it which changes it into liquid ends making it gas

liquid nitrogen boils at 77 K or -196° C

Answer:

(a) ₁₉K: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s¹

(b) ₁₀Ne: 1s² 2s² 2p⁶

---

(a) 3

(b) 6

(c) 7

Explanation:

We can state the ground-state electron configuration for each element following Aufbau's principle.

(a) ₁₉K: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s¹

(b) ₁₀Ne: 1s² 2s² 2p⁶

Second part

(a) Al belongs to Group 13 in the Periodic Table. It has 13-10=3 electrons in the valence shell.

(b) O belongs to Group 16 in the Periodic Table. It has 16-10=6 electrons in the valence shell.

(c) F belongs to Group 17 in the Periodic Table. It has 17-10=7 electrons in the valence shell.

Answer:

2-isopropyl-4-methylphenol.

Explanation:

Hey there!

In this case, according to the given information, it turns out possible for us to assign the appropriate IUPAC name of the given compound, by considering that the phenol stands for the parent chain and we have isopropyl methyl radicals which the former is called first due to the alphabet consideration.

In such a way, the name would be 2-isopropyl-4-methylphenol.

Regards!

With the help of hess's law:

ΔHf(MnO)=−248.9 kJ−12(272.0) kJ=−384.9 kJ(per mole) Δ H f ( M n O ) = − 248.9 k J − 1 2 ( 272.0 ) k J = − 384.9 k J ( p e r m o l e )

Hess's law of constant heat summation, also known simply as Hess' law, is a relationship in physical chemistry named after Germain Hess, a Swiss-born Russian chemist and physician who published it in 1840.

Moreover, hess's Law of Constant Heat Summation (or just Hess's Law) states that regardless of the multiple stages or steps of a reaction, the total enthalpy change for the reaction is the sum of all changes.

Therefore, hess' law is based on the state function character of enthalpy and the first law of thermodynamics. Energy (enthalpy) of a system (molecule) is a state function.

Learn more about hess's law:

https://brainly.com/question/14561923

#SPJ6

Explanation:

ethoxypropane

Ch3-ch2-o-ch2-ch2-och3

Answer:

Work

Explanation:

Formula for work is given by;

Work = force × distance.

It is clear from this formula that Work depends on force and distance.

This means that force and distance are independent of the workdone and so they are classified as independent variables while work will be the dependent variable.

Answer:

The choose (d)

d. polysaccharides

Answer:

CCl4 can neither form H-bonds with water molecules nor can it break H-bonds in water molecules. Therefore, it is insoluble in water. Ethanol is a polar compound and can form H-bonds with water, which is a polar solvent. Therefore,it is miscible with water in all proportions

Explanation:

FIRSTLY WATER MOLECULES CONTAIN ONE OXYGEN AND TWO HYDROGEN(H2O) .HENCE IN THIS STRUCTURE THE BOND BETWEEN OXYGEN AND HYDROGEN IS COVALENT AND POLARIZABLE .HENCE OXYGEN ATOM ATTRACTS ELECTRONS MORE STRONGLY TOWARDS INWARDS AS COMPARE TO 2 HYDROGEN ATOMS. DUE TO WHICH OXYGEN ATOM GET SLIGHTLY NEGATIVE CHARGE AND 2 HYDROGEN OCCUPY SLIGHTLY POSITIVE CHARGE THAT MAKE WATER A POLAR MOLECULE. :NOW IN ETHANOL(CH3CH2OH),ETHANOL MOLECULE IS FORMED BY 2 CARBON ATOM JOINED BY SINGLE BOND WHICH IS NOT POLAR.IN β CARBON OF ETANOL CARBON IS BONDED TO 3 HYDROGEN ATOMS WHICH MAKES IT NON POLAR DUE TO SYMMETRY BUT α CARBON HAS 2 HYDROGEN AND 1 OH- ION (SAME AS IN THE CASE OF WATER MOLECULE) SO THIS CARBON ATOM BECAMES POLAR AND HENCE ETHANOL MOLECULES BECAMES POLAR. NOW WE KNOW THAT SAME CHARGE REPEL EACH OTHER AND UNLIKE CHARGES ATTRACTS EACH OTHER SO THE SLIGHTHLY POSITIVE CHARGE OF WATER MOLECULE MAKES A BOND WITH THE.

Answer:

the scientific name of lion is

Panthera leo

mass = 12.2 g NaOH

n

Step 1: Calculate the molar mass of NaOH.

molar mass = (22.99 g/mol × 1) + (16.00 g/mol × 1) + (1.008 g/mol × 1)

molar mass = 39.998 g/mol

Step 2: Calculate the number of moles of NaOH.

n = mass / molar mass

n = 12.2 g / 39.998 g/mol

n = 0.31 mol

Therefore, the number of moles of NaOH is 0.31 mol.

#ILoveChemistry

Answer:

ANSWERRRRRRRRRRRR BBBBBBBBB

Explanation:

Calculate the molar mass of NaOH.

molar mass = (22.99 g/mol × 1) + (16.00 g/mol × 1) + (1.008 g/mol × 1)

molar mass = 39.998 g/mol

Step 2: Calculate the number of moles of NaOH.

n = mass / molar mass

n = 12.2 g / 39.998 g/mol

n = 0.31 mol

Therefore, the number of moles of NaOH is 0.31 mol.

Answer:

48

Explanation:

Answer:

The answer is C.

Explanation:

In the chemical equation in C, there are 15 Carbon atoms and 1 Phosphorus atom in PC15, and 3 Hydrogen atoms and 6 Oxygen atoms in 3H2O on the left hand side. On the right hand side, there are 3 Hydrogen atoms, 1 Phosphorus atom and 46 Oxygen atoms in H3PO46, and 5 Hydrogen atoms and 5 Chlorine atoms in 5HCl.

Therefore, tallying up, there are 6 Oxygen atoms on the left hand side and 46 Oxygen atoms on the right hand side. This means the chemical equation in C is unbalanced.

Hope this helped!

Answer:

a, d and e. are true.

Explanation:

The reaction that occurs is:

Na2CO3(aq) + CaCl2(aq) → CaCO3(s) + 2NaCl

In ideal conditions, the percent yield of the reaction must be 100%. All explanations about why the student could not collect all precipitate are right:

a. The combined reactants were not stirred before filtering the precipitate. Not stirring could not promote all the reaction. TRUE.

b. The student did not completely dry the precipitate before weighing it. If the student don't dry the precipitate, the mass of precipitate must be higher producing a percent yield > 100%. FALSE.

c. The precipitate was not washed prior to drying. Produce more mass. FALSE.

d. A rubber policeman was not used to scrape precipitate from the beaker. If the student doesn't collect all the precipitate the percent yield could be < 100%.. TRUE.

e. The filter paper was not wetted with water prior to filtering the precipitate. TRUE. If you don't wet the filter paper you can lose a part of precipitate from the walls of this one.

Answer:

The volume of the sample is 17.4L

Explanation:

The reaction that occurs requires the same amount of CO and NO. As the moles added of both reactants are the same you don't have any limiting reactant. The only thing we need is the reaction where 4 moles of gases (2mol CO + 2mol NO) produce 3 moles of gases (2mol CO2 + 1mol N2). The moles produced are:

0.1800mol + 0.1800mol reactants =

0.3600mol reactant * (3mol products / 4mol reactants) = 0.2700 moles products.

Using Avogadro's law (States the moles of a gas are directly proportional to its pressure under constant temperature and pressure) we can find the volume of the products:

V1n2 = V2n1

Where V is volume and n moles of 1, initial state and 2, final state of the gas

Replacing:

V1 = 23.2L

n2 = 0.2700 moles

V2 = ??

n1 = 0.3600 moles

23.2L*0.2700mol = V2*0.3600moles

17.4L = V2

Explanation:

For preparing lyophobic sol, the substance in bulk is broken down into particles of colloidal dimensions (Dispersion) or aggregating smaller particles into particles of colloidal dimensions (condensation).

Answer:

I don't know sorry siso

Explanation:

I don't know

Answer: The pH of the resulting solution will be 3.60

Explanation:

Molarity is calculated by using the equation:

[tex]\text{Molarity}=\frac{\text{Moles}}{\text{Volume}}[/tex] ......(1)

We are given:

Molarity of formic acid = 0.100 M

Molarity of potassium formate = 0.100 M

Volume of solution = 420 mL = 0.420 L (Conversion factor: 1 L = 1000 mL)

Putting values in equation 1, we get:

[tex]\text{Moles of formic acid}=(0.100mol/L\times 0.420L)=0.0420mol[/tex]

[tex]\text{Moles of potassium formate}=(0.100mol/L\times 0.420L)=0.042mol[/tex]

Molarity of KOH = 1.00 M

Volume of solution = 7 mL = 0.007 L

Putting values in equation 1, we get:

[tex]\text{Moles of KOH}=(1mol/L\times 0.007L)=0.007mol[/tex]

The chemical equation for the reaction of formic acid and KOH follows:

                 [tex]HCOOH+KOH\rightleftharpoons HCOOK+H_2O[/tex]

I:                   0.042     0.007       0.042

C:                -0.007    -0.007     +0.007

E:                  0.035         -           0.049

Volume of solution = [420 + 7] = 427 mL = 0.427 L

To calculate the pH of the acidic buffer, the equation for Henderson-Hasselbalch is used:

[tex]pH=pK_a+ \log \frac{\text{[conjugate base]}}{\text{[acid]}}[/tex] .......(2)

Given values:

[tex][HCOOK]=\frac{0.049}{0.427}[/tex]

[tex][HCOOH]=\frac{0.035}{0.427}[/tex]

[tex]pK_a=3.75[/tex]

Putting values in equation 2, we get:

[tex]pH=3.75-\log \frac{(0.049/0.427)}{(0.035/0.427)}\\\\pH=3.75-0.146\\\\pH=3.60[/tex]

Hence, the pH of the resulting solution will be 3.60