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What do transfer RNA molecules do during protein synthesis? copy the coded message from the DNA and carry it into the cytoplasm copy the coded message from the DNA and carry it into the nucleus carry amino acids and add them to the growing protein copy the coded message from the protein and carry it into the nucleus

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What do transfer RNA molecules do during protein synthesis? copy the coded message from the DNA and carry it into the cytoplasm copy the coded message from the DNA and carry it into the nucleus carry amino acids and add them to the growing protein copy the coded message from the protein and carry it into the nucleus

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What energy-carrying molecules are created during glycolysis?

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What energy-carrying molecules are created during glycolysis?

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How many molecules of DNA would result from one molecule after four cycles of PCR A.4 B.16 C.32 D.2

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Answer: B.16

Explanation

The polymerase chain reaction (PCR) is a technique used in molecular biology to make millions of copies DNA from a small amount of it. To acomplish this, short segments of DNA called primers are designed to each chain of the DNA that is going to be copied. Then, the DNA polymerase adds nucleotides to theose primers that will be complementary to the DNA chains. After one molecule is amplified, a new molecule is amplified using that one and so on and so forth. Then, 2 chains are amplified in one cycle to get 2 molecules (with two chains each) Thereby, the replication rate of DNA is exponential, then it is calculated as:

1 x (2^4) = 16 DNA molecules.

1= molecule

2= chains per molecule

4= number of cycles

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Which statement best describes the use of catalytic converters in automobiles? A. They decrease the rate of the reactions that produce harmful gases. B. They oxidize hydrocarbons to form less toxic gases. C. They combine the larger hydrocarbon molecules with smaller ones. D. They increase reaction temperature for cleaner burning.

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Answer:  B. They oxidize hydrocarbons to form less toxic gases.

Explanation:

A catalytic converter is a device which is used in automobile engine to convert the harmful gaseous exhaust into a less toxic pollutant after the process of combustion of the fuel. It conducts an internal redox (oxidation-reduction) reaction in the automobile engine to facilitate such conversion.

On the basis of the above information, They oxidize hydrocarbons to form less toxic gases is the correct option.

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The main difference between gases and liquids is that in gases A.the molecules are moving faster b.the forces between molecules are greater c.the distance between molecules are greater d.the molecules collide more frequently

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The main difference between gases and liquids is that in gases A.the molecules are moving faster b.the forces between molecules are greater c.the distance between molecules are greater d.the molecules collide more frequently

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Why is water an excellent solvent for most ionic compounds and polar covalent molecules but not for non-polar compounds? A) Water is a polar molecule. B) Water has a charge like an ion. C) Water is a deionizing substance. D) Water molecules have an unusually high kinetic energy in the liquid state.

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A)Water is a polar molecule. When talking about solubility, the rule that “like dissolves like” is usually correct. This means that polar substances are soluble in other polar substances. This occurs because the opposite partially charged ends of different polar molecules are attracted to each other. Similarly, the partially charged ends of polar molecules will be even more attracted to the charged ends of an ionic compound’s molecule. This is why,for example, table salt/ NaCl, which is an ionic compound, dissolves in water. 

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Anonymous 5 years ago A molecule that can be used as a molecular clock has a neutral mutation rate of one mutation per 5 million years. How many years ago did two species share a common ancestor if the molecules found in these two species differ by a total of eight mutations? Answer a) 1.5 million years b) 10 million years c) 20 million years d) 40 million years

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Anonymous 5 years ago A molecule that can be used as a molecular clock has a neutral mutation rate of one mutation per 5 million years. How many years ago did two species share a common ancestor if the molecules found in these two species differ by a total of eight mutations? Answer a) 1.5 million years b) 10 million years c) 20 million years d) 40 million years

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What is the function of the Golgi apparatus? A.It makes protein, lipid, and carbohydrate molecules. B.It makes ATP by breaking down food molecules. C.It stores molecules made in the ER. D.It packages and ships molecules made in the ER. NEED HELP FAST PLZ AND THX

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What is the function of the Golgi apparatus? A.It makes protein, lipid, and carbohydrate molecules. B.It makes ATP by breaking down food molecules. C.It stores molecules made in the ER. D.It packages and ships molecules made in the ER. NEED HELP FAST PLZ AND THX

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True or false, both mass spectrometry and infrared spectroscopy involve the interaction of molecules with electromagnetic energy

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Answered by answersmine AT 22/10/2019 – 04:48 AM

Yes, it is true, both mass spectrometry and infrared spectroscopy involve interaction of molecules with electromagnetic waves. ;Mass spectrometry method is used to determine the mass of a substance while infrared spectroscopy is used to determine the functional groups in molecules. Both methods involve the analysis of electromagnetic light interaction with molecules. 

Post your answer

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– How many moles of NaHCO3 can be produced from 125 mol of NaCl – How many moles Of H2O are produced when 6 mol of O2 is consumed in burning methyl alcohol, CH3OH, according to the following equation? – Solutions of iron(III) chloride, FeCl3, are used in photoengraving and to make ink. This compound can be made by the following reaction. a. How many moles of FeCl3 form from 31 mol of Cl2? b. How many moles of Fe are needed to combine with 5 mol of Cl2 by this reaction? c. If 0.62 mol of Fe is to be used by this reaction, how many moles of FeCl3 form? – Ammonia is produced synthetically by the reaction: a. Is this an exothermic or endothermic process? b. How many moles of NH3 are formed when 1 mol of N2 reacts with hydrogen? c. If 18 x 1023 molecules of H2 react with nitrogen, how many moles of NH3 are produced?

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A positive cahnge of enthalpy, ΔH rxn = + 55 kJ/mol, for the forward reaction means that the reaction is endothermic, i.e. the reactants absorb energy and the products are higher in energy.

Activation energy is the difference in the energy level of the reactants and the peak in the potential energy diagram (the energy of the transition state).

For an endothermic reaction, the products will be closer in energy to the transition state than what the reactans will be; so, the activation energy of the reversed reaction is lower than the activation energy of the forward reaction.

Activation energy of reverse and forward reactions is related by:

Activation energy of reverse rxn = Activation energy of forward rxn – ΔH rxn

=> Activiation energy of reverse rxn = 102 kJ/mol – 55 kJ/mol = 47 kJ/mol

Answer: 47 kJ/mol

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What is the mass of 2.50 × 1025 molecules of sugar (c12h22o11)?

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The unknown of this problem is the experimental percent of water in the compound in order to remove the water of hydrogen, given the following:

Mass of crucible, cover and contents before heating                               23.54 g
Mass of empty crucible and cover                                                            18.82 g
Mass of crucible, cover, and contents after heating to constant mass     20.94 g

In order to get the answer, determine the following:

Mass of hydrated salt used                          = 23.54 g – 18.82 g = 4.72 g
Mass of dehydrated salt after heating          = 20.94 g – 18.82 g = 2.12 g
Mass of water liberated from salt                 = 4.72 g – 2.12 g = 2.60 g

Then solve the percent of water in the hydrated salt by:

% water = (mass of water / mass of hydrated salt) x 100
% water = 2.60 g / 4.72 g x 100
% water = 55.08 % in the compound 

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As a substance changes phase from a gas to liquid to solid: A- The spacing between molecules increases. B- It's density generally increases. C- The spacing between molecules is not affected. D- It undergoes chemical change.

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As a substance changes phase from a gas to liquid to solid: A- The spacing between molecules increases. B- It’s density generally increases. C- The spacing between molecules is not affected. D- It undergoes chemical change.

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WORTH 15 FOR 2 EASY QUESTIONS MULTIPLE CHOICE SECOND QUESTIONS EVEN EASIER THAN THE FIRST IM PRETTY SURE THE ANSWER IS C JUST CHECKING Which of the following conditions would likely prevent the assembly and survival of new kinds of organic molecules on Earth today? A. the presence of bacteria and other life forms B. the presence of carbon dioxide C. the supply of atoms that serve as raw material D. the light and warmth from the sun 2. Several different species make up a A. family. B. genus. C. kingdom. D. phylum.

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Answer:

The integumentary system covers the surface of the body is true about the integumentry system.

Explanation:

The integumentary system includes the skin, nails, glands, hairs, and nerves. Its main role is to act as a barrier to protect the body from the outside environment. It also retains body fluids, regulates body temperature, eliminates waste products, and protects against disease.

The integumentary system is the largest organ in the body that covers the surface of the body.

Thus, The integumentary system covers the surface of the body is the true statement about the integumentry system.

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Which characteristic of water allows its molecules to form hydrogen bonds

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This problem is to apply Roult’s Law.

Roult’s Law states that the vapor pressure, p, of a solution of a non-volatile solute is equal to the vapor pressure of the pure solvent, Po solv, times the mole fraction of the solvent, Xsolv

p = Xsolv * Po sol

X solv = number of moles of solvent / number of moles of solution

The solvent is water and the solute (not volatile) is glycerin.

Number of moles = mass in grams / molar mass

mass of water = 132 ml * 1 g/ml = 132 g

molar mass of water = 18 g/mol

=> number of moles of water = 132 g / 18 g/mol = 7.33333 mol

mass of glycerin = 27.2 g

molar mass of glycerin:, C3H8O3: 3 * 12 g/mol + 8 * 1 g/mol + 3*16 g/mol = 92 g/mol

number of moles of glycerin = 27.2g / 92 g/mol = 0.29565

total number of moles = 7.33333 moles + 0.29565 moles = 7.62898 moles

=> X solv = 7.33333 / 7.62898 = 0.96125

=> p = 0.96125 * 31.8 torr ≈ 30.57 torr ≈ 30.6 torr.

Answer: 30.6 torr

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At equilibrium what happens to the random movement of molecules

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Answer:

Rate of movement of snail, s = 0.25 meters per hour

Explanation:

It is given that,

Distance covered by snail, d = 0.5 m

The snail moved this distance in 2 hours

Since, 1 hour = 3600 seconds

So, 2 hour = 7200 seconds

We have to find the rate of movement of snail i.e. s

s=dfrac{d}{t}

So,

s=dfrac{0.5}{7200}

s = 0.000069 m/s

Converting m/s to m/h

So, s = 0.248 m/h

or s = 0.25 meters per hour

Hence, the correct option is (d)

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Which characteristic of water allows its molecules to form hydrogen bonds? The water molecule is polar. Water has a low specific heat. Ionic bonds hold the water molecule together. Water expands as it freezes.

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Answer:

1) Water has very high specific heat.

2) It expands when it freezes

3) ability to dissolve in ionic substances

4) Water molecules at the surface experience fewer hydrogen bonds than water molecules within the liquid.

Explanation:

1) Water molecules due to their high specific heat , undergo relatively less increase in temperature after absorbing heat. So they prevent their adjoining area to experience sharp increase in temperature.

2) Water is an example which expands on freezing. In it , large spaces are left between molecules when it cools. It happens because hydrogen bonds prevent any two molecules to come very close thereby  creating gaps. This gap is filled up when ice melts , which results in overall reduction in volume of water.

3) Uneven distribution of charge results in water molecules becoming polar in nature . A polar substance  can be dissolved in polar solvents only.

4) It is due to property of surface tension. Property  of surface tension results due to molecules of water near the surface experiencing a  net downward  force due to hydrogen bonds . It is due to fewer hydrogen bonds made by them.

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Methanol is an important solvent. it is also an important starting material for the synthesis of other molecules. most methanol today is obtained from the

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Methanol is an important solvent. it is also an important starting material for the synthesis of other molecules. most methanol today is obtained from the

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A scientist adds heat to each of the following substances. Which will probably absorb the most heat before its temperature changes significantly? 50 g of solid copper 50 g of solid iron 50 g of liquid water 50 g of sand Question 2(Multiple Choice Worth 2 points) A drop of water placed on a smooth, dry surface will form a dome-shaped droplet instead of flowing outward in different directions. Which of these best explains this observation? The bonds between hydrogen and oxygen atoms are very strong. The electrons in the atoms attract the electrons in the other atoms. Water molecules at the surface experience fewer hydrogen bonds than water molecules within the liquid. Water molecules near the surface produce more buoyant force than water molecules within the liquid. Question 3(Multiple Choice Worth 2 points) Which of these best explains what happens when the ionic substance calcium chloride (CaCl2) dissolves in water? The oxygen atoms in the water molecules are attracted to the Ca2+ ions. The oxygen atoms in the water molecules are attracted to the Cl− ions. The hydrogen atoms in the water molecules are attracted to the Ca2+ ions. The oxygen atoms in the water molecules are attracted to the H+ ions. Question 4(Multiple Choice Worth 2 points) Which of these statements about water is true? Its atoms share electrons equally. It can dissolve all known substances. Its molecules are farther apart in the solid state than in the liquid state. It has a lower specific heat than nearly all known metals.

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The gravitational force Fg between two objects is given by the equation:

Fg=(G*m₁*m₂)/r₂, where G=6.67*10^-11 m³ kg⁻¹ s⁻² is the gravitational constant, m₁ and m₂ are the masses of the two bodies and r is the distance between those bodies. 

Due to the gravitational attraction the pencil and the eraser will attract if we there is no friction on the surface. 

m₁=10 g=0.01 kg is the mass of the pencil
m₂=20 g=0.02 kg is the mass of the eraser
r=2.5 cm = 0.025 m

First we calculate the Fg:

Fg={(6.67*10^-11)*0.01*0.02}/(0.025²)=2.1344*10^-11 N

To get the velocity v of the pencil:

v²=2as, where a is the acceleration of the pencil and s is the path. In our case s=r so we can write:

v²=2ar

a=Fg/m₁= 2.133*10^-9 m/s²

v²=2*(2.133*10^-9)*0.025=1.0665*10^-10

v=√(1.0665*10^-10)=1.0327*10^-5 m/s

We have the velocity and the acceleration, so we can calculate the time t with the equation:

t=v/a=(1.0327*10^-5)/(2.133*10^-9)=4841.6 s

1 hour has 3600 s so when we divide time t in seconds by 3600 we get time T in hours:

T=t/3600=4841.6/3600=1.3449 h. 

So the time for the pencil and eraser to touch is T=1.3449 hours. 

Also time T can be expressed like T= 1h and 20 mins and 41.64 s

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Why might scientists be interested in making transgenic organisms? Transgenic organisms glow in the dark and provide a light source in dark places. Transgenic organisms can produce a desired product that may benefit other organisms. Transgenic organisms can be used to cut strands of DNA molecules into fragments. Transgenic organisms can be used as a medium to transfer foreign DNA into a host cell

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Answer:

The integumentary system covers the surface of the body is true about the integumentry system.

Explanation:

The integumentary system includes the skin, nails, glands, hairs, and nerves. Its main role is to act as a barrier to protect the body from the outside environment. It also retains body fluids, regulates body temperature, eliminates waste products, and protects against disease.

The integumentary system is the largest organ in the body that covers the surface of the body.

Thus, The integumentary system covers the surface of the body is the true statement about the integumentry system.

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Areas near oceans or large lakes tend to have more moderate climates than do areas far from large bodies of water. Which of these statements best explains this observation? Hydrogen and oxygen atoms share electrons in a water molecule. Lakes and oceans contain dissolved solids. Water has a very high specific heat. Water produces buoyant forces. Question 2(Multiple Choice Worth 2 points) A scientist discovers a new substance. The molecules of the substance form hydrogen bonds with each other. When the molecules lose a lot of energy, the hydrogen bonds hold them relatively far apart. Based on this information, what can the scientist infer about the substance? It expands when it freezes. It is highly colored. It exists only as a gas. It does not dissolve ionic compounds. Question 3(Multiple Choice Worth 2 points) Which of the following properties of water is due primarily to the uneven distribution of charge between the hydrogen and oxygen atoms? its color its taste its ability to dissolve ionic substances its ability to produce buoyant forces Question 4(Multiple Choice Worth 2 points) A drop of water placed on a smooth, dry surface will form a dome-shaped droplet instead of flowing outward in different directions. Which of these best explains this observation? The bonds between hydrogen and oxygen atoms are very strong. The electrons in the atoms attract the electrons in the other atoms. Water molecules at the surface experience fewer hydrogen bonds than water molecules within the liquid. Water molecules near the surface produce more buoyant force than water molecules within the liquid.

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The gravitational force Fg between two objects is given by the equation:

Fg=(G*m₁*m₂)/r₂, where G=6.67*10^-11 m³ kg⁻¹ s⁻² is the gravitational constant, m₁ and m₂ are the masses of the two bodies and r is the distance between those bodies. 

Due to the gravitational attraction the pencil and the eraser will attract if we there is no friction on the surface. 

m₁=10 g=0.01 kg is the mass of the pencil
m₂=20 g=0.02 kg is the mass of the eraser
r=2.5 cm = 0.025 m

First we calculate the Fg:

Fg={(6.67*10^-11)*0.01*0.02}/(0.025²)=2.1344*10^-11 N

To get the velocity v of the pencil:

v²=2as, where a is the acceleration of the pencil and s is the path. In our case s=r so we can write:

v²=2ar

a=Fg/m₁= 2.133*10^-9 m/s²

v²=2*(2.133*10^-9)*0.025=1.0665*10^-10

v=√(1.0665*10^-10)=1.0327*10^-5 m/s

We have the velocity and the acceleration, so we can calculate the time t with the equation:

t=v/a=(1.0327*10^-5)/(2.133*10^-9)=4841.6 s

1 hour has 3600 s so when we divide time t in seconds by 3600 we get time T in hours:

T=t/3600=4841.6/3600=1.3449 h. 

So the time for the pencil and eraser to touch is T=1.3449 hours. 

Also time T can be expressed like T= 1h and 20 mins and 41.64 s

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How many carbon dioxide molecules are produced by the complete aerobic breakdown of one glucose molecule

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How many carbon dioxide molecules are produced by the complete aerobic breakdown of one glucose molecule

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How is the volatility of a substance related to the intermolecular forces present within the substance? how is the volatility of a substance related to the intermolecular forces present within the substance? the weaker the intermolecular forces, the more likely it is that molecules are to evaporate at a given temperature, making the liquid more volatile. the volatility of a substance does not depend on the intermolecular forces present within the substance. the stronger the intermolecular forces, the more likely it is that molecules are to evaporate at a given temperature, making the liquid more volatile?

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This problem is to apply Roult’s Law.

Roult’s Law states that the vapor pressure, p, of a solution of a non-volatile solute is equal to the vapor pressure of the pure solvent, Po solv, times the mole fraction of the solvent, Xsolv

p = Xsolv * Po sol

X solv = number of moles of solvent / number of moles of solution

The solvent is water and the solute (not volatile) is glycerin.

Number of moles = mass in grams / molar mass

mass of water = 132 ml * 1 g/ml = 132 g

molar mass of water = 18 g/mol

=> number of moles of water = 132 g / 18 g/mol = 7.33333 mol

mass of glycerin = 27.2 g

molar mass of glycerin:, C3H8O3: 3 * 12 g/mol + 8 * 1 g/mol + 3*16 g/mol = 92 g/mol

number of moles of glycerin = 27.2g / 92 g/mol = 0.29565

total number of moles = 7.33333 moles + 0.29565 moles = 7.62898 moles

=> X solv = 7.33333 / 7.62898 = 0.96125

=> p = 0.96125 * 31.8 torr ≈ 30.57 torr ≈ 30.6 torr.

Answer: 30.6 torr

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A 1.50-g sample of hydrated copper(ii) sulfatewas heated carefully until it had changed completely to anhydrous copper(ii) sulfate () with a mass of 0.957 g. determine the value of x. [this number is called the number of waters of hydration of copper(ii) sulfate. it specifies the number of water molecules per formula unit of in the hydrated crystal.]

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This problem is to apply Roult’s Law.

Roult’s Law states that the vapor pressure, p, of a solution of a non-volatile solute is equal to the vapor pressure of the pure solvent, Po solv, times the mole fraction of the solvent, Xsolv

p = Xsolv * Po sol

X solv = number of moles of solvent / number of moles of solution

The solvent is water and the solute (not volatile) is glycerin.

Number of moles = mass in grams / molar mass

mass of water = 132 ml * 1 g/ml = 132 g

molar mass of water = 18 g/mol

=> number of moles of water = 132 g / 18 g/mol = 7.33333 mol

mass of glycerin = 27.2 g

molar mass of glycerin:, C3H8O3: 3 * 12 g/mol + 8 * 1 g/mol + 3*16 g/mol = 92 g/mol

number of moles of glycerin = 27.2g / 92 g/mol = 0.29565

total number of moles = 7.33333 moles + 0.29565 moles = 7.62898 moles

=> X solv = 7.33333 / 7.62898 = 0.96125

=> p = 0.96125 * 31.8 torr ≈ 30.57 torr ≈ 30.6 torr.

Answer: 30.6 torr

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Identify the phase in which the water molecules are closest together. identify the phase in which the water molecules are closest together. liquid gas solid dry ice

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This problem is to apply Roult’s Law.

Roult’s Law states that the vapor pressure, p, of a solution of a non-volatile solute is equal to the vapor pressure of the pure solvent, Po solv, times the mole fraction of the solvent, Xsolv

p = Xsolv * Po sol

X solv = number of moles of solvent / number of moles of solution

The solvent is water and the solute (not volatile) is glycerin.

Number of moles = mass in grams / molar mass

mass of water = 132 ml * 1 g/ml = 132 g

molar mass of water = 18 g/mol

=> number of moles of water = 132 g / 18 g/mol = 7.33333 mol

mass of glycerin = 27.2 g

molar mass of glycerin:, C3H8O3: 3 * 12 g/mol + 8 * 1 g/mol + 3*16 g/mol = 92 g/mol

number of moles of glycerin = 27.2g / 92 g/mol = 0.29565

total number of moles = 7.33333 moles + 0.29565 moles = 7.62898 moles

=> X solv = 7.33333 / 7.62898 = 0.96125

=> p = 0.96125 * 31.8 torr ≈ 30.57 torr ≈ 30.6 torr.

Answer: 30.6 torr

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Molecules that have the same chemical formula but have different molecular structures are

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The right answer is Transgenic organisms can produce a desired product that may benefit other organisms.

A transgenic organism contains DNA combining  stably integrated in all its cells. In other words, the organism, be it a plant, an animal or a microorganism, has a new piece of DNA embedded in it. a chromosome in each of its cells. This “new piece” of DNA usually contains a gene from another organism (plant, animal or other) that has been modified to be expressed in the new  organization. A transgenic organism may even possess the DNA of another organism of the same species. The inserted gene can be called the transgene.

Currently, diabetics are treated by injecting insulin from either a healthy human donor or cultures of genetically modified (transgenic) bacteria that secrete the protein.

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