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Answer:

The answer to your question is given below

Explanation:

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

Mass of cholesterol (in μg) = 203 μg

Mass of cholesterol (in Kg) =?

The following conversion scale can be used to convert micro grams (μg) to kilogram (kg).

1 μg = 1×10¯⁹ Kg

Therefore,

203 μg = 203 μg × 1×10¯⁹ Kg / 1 μg

203 μg = 2.03×10¯⁷ Kg

Thus, 203 μg is equivalent to 2.03×10¯⁷ Kg

Answer: Moseley's experiments in X-ray spectroscopy showed directly from their physics that cobalt and nickel have the different atomic numbers, 27 and 28, and that they are placed in the Periodic Table correctly by Moseley's objective measurements of their atomic numbers.

Explanation:

Answer:

12 moles of F₂

Explanation:

We'll begin by writing the balanced equation for the reaction. This is illustrated below:

N₂ + 3F₂ —> 2NF₃

From the balanced equation above,

3 moles of F₂ reacted to produce 2 moles of NF₃.

Finally, we shall determine the number of mole of F₂ needed to produce 8 moles of NF₃. This can be obtained as illustrated below:

From the balanced equation above,

3 moles of F₂ reacted to produce 2 moles of NF₃.

Therefore, Xmol of F₂ will react to produce 8 moles of NF₃ i.e

Xmol of F₂ = (3 × 8)/2

Xmol of F₂ = 12 moles

Thus, 12 moles of F₂ is needed for the reaction.

Answer:

Ba(NO₃)₂(aq) + Na₂SO₄(aq) ⇒ BaSO₄(s) + 2 NaNO₃(aq)

Explanation:

Let's consider the unbalanced double displacement equation for the reaction of an aqueous solution of barium nitrate and an aqueous solution of sodium sulfate.

Ba(NO₃)₂(aq) + Na₂SO₄(aq) ⇒ BaSO₄(s) + NaNO₃(aq)

To get the balanced equation, we will multiply NaNO₃(aq) by 2.

Ba(NO₃)₂(aq) + Na₂SO₄(aq) ⇒ BaSO₄(s) + 2 NaNO₃(aq)

Answer:

40.5%  is abundance of X-122

Explanation:

we know there are two naturally occurring isotopes of X, X-120  and X-122.

First of all we will set the fraction for both isotopes

X for the isotopes having mass 122

1-x for isotopes having mass 12 0

The average atomic mass of X is 120.81 amu

we will use the following equation,

122x + 120 (1-x) = 120.81

122x + 120 - 120x = 120.81

122x- 120x = 120.81 -120

2x = 0.81

x= 0.81/2

x= 0.405

0.405 × 100 = 40.5%

40.5%  is abundance of X-122 because we solve the fraction x.

now we will calculate the abundance of X-120.

(1-x)

1 - 0.405 = 0.595

0.595  × 100 = 59.5 %

59.5 %  for X-120.

Answer:

.133

Explanation:

Dissolution of solute lowers the vapor pressure of solvent .

Relative lowering by non -volatile solute is equal to mole fraction of solute dissolved .

Vapor pressure of pure water is 2.33 k Pa

Lowering of vapor pressure = 2.33 - 2.02 = .31 k Pa .

relative lowering = .31 / 2.33 = .133

relative lowering will be equal to mole fraction of non volatile solute like NaCl

so mole fraction of NaCl dissolved = .133

Answer:

if its a neutral atom there should be 6 electrons because there are 6 protons

Explanation:

Answer:

n-Pentane

Explanation:

All molecules possess dispersion forces. It is possible in non-polar molecules that a temporary distortion in the electron distribution of one molecule can affect the electron distribution in a neighboring molecule. This is known as  induced dipole, induced dipole forces.

However, this  induced dipole, induced dipole forces depends on the shape of the molecule. Molecules of n-pentane are capable of better interaction via  induced dipole, induced dipole forces since the molecules interact over the entire length of the molecule rather than neopentane which is more compact and nearly spherical.

Answer:

Ground water

Explanation:

The ground water reservoir is found underground in cracks and spaces in the soil, sand and rock.

Ground water is a very important portion of the water cycle where water is stored in an aquifer.

Aquifers are porous and permeable formations that stores ground water within them.

In this manner, ground water system is recharged by infiltration of water from the surface. Water percolates and collects inside an aquifer in this manner.

Answer:

Ground Water

Explanation:

Answer: Once nitrogen is converted into compounds like ammonium and nitrate, these can be taken up from soils by plants and then the nitrogen can be used to form macromolecules like proteins and nucleic acids (DNA and RNA).

The answer is proteins

Answer:

V = 5.6 L

Explanation:

Given data:

Number of moles of C₄H₁₀ = 0.25 mol

Temperature = standard = 273.15 K

Pressure = standard = 1 atm

Volume of C₄H₁₀ = ?

Solution:

Formula:

PV = nRT

R = general gas constant = 0.0821 atm.L /mol.K

1 atm × V = 0.25 mol ×  0.0821 atm.L /mol.K × 273.15 K

V = 5.6 atm.L/ 1 atm

V = 5.6 L

Answer:

C. 43 kJ

Explanation:

Bond energy (bond enthalpy (H) or bond strength) is the amount of energy required to break a bond. The bond energy is used to determine the strength of a chemical bond.

The bond energy is the difference between the energy of the reactants and the energy of the products. The bond energy is given by:

[tex]\Delta H=\Sigma Bond\ energy\ reactants-\Sigma Bond\ energy\ products\\\\Where \ \Delta H=bond\ energy\ or\ energy\ released\\\\Given\ that\ \Delta H=25\ kJ,\Sigma Bond\ energy\ reactants=68\ kJ, Hence:\\\\\Delta H=\Sigma Bond\ energy\ reactants-\Sigma Bond\ energy\ products\\\\Substituting:\\\\25\ kJ=68\ kJ- \Sigma Bond\ energy\ products\\\\ \Sigma Bond\ energy\ products=68\ kJ-25\ kJ\\\\ \Sigma Bond\ energy\ products=43\ kJ\\[/tex]

Answer: is simply C.

Answer:

C 1,868 years

Explanation:

I just took the test - I tried doing the math and was close but couldn't get it exact; so I guessed and I was correct :)

Answer:

1,868 years

Explanation:

Answer: Either [tex]C_5H_6O[/tex]  or [tex]C_{10}H_{12}O_2[/tex]

Explanation:

Molecular formula is the chemical formula which depicts the actual number of atoms of each element present in the compound.  

Empirical formula is the simplest chemical formula which depicts the whole number of atoms of each element present in the compound.  

The empirical formula is [tex]C_5H_6O[/tex]

Now we have to calculate the molecular formula:

[tex]n=\frac{\text{Molecular weight }}{\text{Equivalent weight}}[/tex]

n is a whole number

The molecular formula could be=[tex]1\times C_5H_6O=C_5H_6O[/tex]

Thus molecular formula could be = [tex]2\times C_5H_6O=C_{10}H_{12}O_2[/tex]

Answer:

Explanation:

λ  =  [tex]10^8[/tex]   meters

Explanation:

f : frequency

c :  velocity of light

λ  : wavelength

f  =  c/λ

λ  =  c /f

c  =  2.99  ⋅ [tex]10^8[/tex] m/ s

λ  =  [tex]10^8[/tex] meters

Answer: absorbs energy

Explanation:

Answer:

releases energy

Explanation:

Answer:

×

Explanation:

FALSE BECAUSE NOT OCEAN IT IS ALL

Answer:

0.576M and 0.655m

Explanation:

...Dissolves 15.0g of styrene (C₈H₈) in 250.mL of a solvent with a density of 0.88g/mL...

Molarity is defined as moles of solute (Styrene in this case) per liter of solution whereas molality is the moles of solute per kg of solvent. Thus, we need to find the moles of styrene, the volume in liters of the solution and the mass in kg of the solvent as follows:

Moles styrene:

Molar mass C₈H₈:

8C = 12.01g/mol*8 = 96.08g/mol

8H = 1.005g/mol* 8 = 8.04g/mol

96.08g/mol + 8.04g/mol = 104.12g/mol

Moles of 15.0g of styrene are:

15.0g * (1mol / 104.12g) = 0.144 moles of styrene

Liters solution:

250mL * (1L / 1000mL) = 0.250L

kg solvent:

250mL * (0.88g/mL) * (1kg / 1000g) = 0.220kg

Molarity is:

0.144 moles / 0.250L =

Molality is:

0.144 moles / 0.220kg =

Answer:

1. nitric acid: sa

2. perchloric acid: sa

3. hydrofluoric acid: wa

Explanation:

A strong acid (sa) is the one that is completely dissociated into ions in water. Conversely, a weak acid (wa) is not completely dissociated in water.

From the options, the strong acids are:

1. nitric acid (HNO₃). It dissociates completely into ions when is dissolved in water, as follows:

HNO₃ → H⁺ + NO₃⁻

2. perchloric acid (HClO₄). It is completely dissociated in water as follows:

HClO₄ → H⁺ + ClO₄⁻

The weak acid is hydrofluoric acid (HF). In water, only a small proportion is dissociated into ions. The proportion of ions formed is given by the equilibrium constant Ka. The dissociation is written by using double arrows:

HF ⇄ H⁺ + F⁻

Answer:

mass= 150 g

volume= 550 cm3

density= mass/ volume

= 150/550

= 0.27 g/cm3

Answer:

1.16 cubic centimeters

Explanation:

Answer:

Strontium is a soluble earth metal with the nuclear number 38. Phosphate is a polyatomic particle containing phosphorus and oxygen molecules. Strontium loses electrons to turn out to be emphatically charged, and phosphate is an adversely charged particle.

Explanation:

When strontium phosphide comes into contact with water, it transforms into a solid that emits poisonous and combustible fumes. It is a highly reactive substance utilized in the production of chemically reactive devices as well as a laboratory reagent. Strontium phosphide is ionic.

Two elements combine to form an ionic compound. Sr is the metal while P is the non-metal in the ionic combination. After transferring its two valence electrons to P to create the phosphide ion, which has a net negative charge of -3, strontium becomes a cation.

Ions are charged particles that form when an atom (or group of atoms) receives or loses an electron, and ionic compounds are composed of these charged particles.

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Answer:

7.07

Explanation:

HA = weak acid = 0.053

A+ = conjugate base = 0.045

Ka = 7.2x10^-8

Ka = [H+][A-]/HA

7 2x10^-8 = [H+][0.045]/0.053

[H+] = 7.2x10^-8 x 0.053/0.045

= 8.48x10^-8

PH = -log[H+]

= -log[8.48x10^-8]

PH = -[login.48 + log10^-8]

PH = -0.928 - (-8)log10

= 7.07

Answer:

There will be an increased span of the melting point of acetanilide

Explanation:

if benzoic acid and acetanilide are mixed in equal amounts, there will be an increased span of the melting point of acetanilide than what is known already. This is because the two compounds have mixed together to become a mixture.

Answer:

Anwser A

Explanation:

Sand dunes are created by wind deposition.

The accumulation of sand that produce the sand dunes is called wind deposition. Therefore, option (A) is correct.

Sand dunes are formed when wind deposits the sand on top of each other. It stays until a small mound starts to form. As the first mound forms, sand builds up on the windward side more and more until the edge of the dune breaks due to its own weight.

When the angle of the dune becomes too big to support the weight,  the collapse of sand dune begins. This is called the angle of repose usually around 30°-34° also depends upon wind speed, grain size, and roundedness of the individual grains.

As these dunes collapse, the sand starts to move in the same direction as the wind. The sand piles up on multiple sides of the dune by changing wind direction and is unable to get the angle of repose such dune never collapses.

Therefore, the sand dunes produce the accumulation of sand through a process called wind deposition.

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