Answer:
Valence electrons are the outermost electrons of an atom, and the number of valence electrons in a metal can be determined by looking at the element's position on the periodic table. Generally, the columns on the periodic table are arranged in order of increasing valence electrons, except for the transition metals. The element's oxidation state can determine the valence electrons for transition metals.
Explanation:
How many moles of sodium hypobromite (NaBrO) should be added to 1.00 L of 0.050 M hypobromous acid
(HBrO) to form a buffer solution of pH 9.15? (Assume that no volume change occurs when the NaBrO is added)
(Ka=2.5x10)
The concentration terms are molality, normality and mole fraction. Molarity can be used to find out the ionic strength of any solution. Therefore, 0.050moles of sodium hypobromite (NaBrO) should be added to 1.00 L of 0.050 M hypobromous acid (HBrO) to form a buffer solution of pH 9.15
What is molarity?Molarity can be calculated by dividing number of moles of solute by volume of solution in litre. Molarity is affected by temperature. Its unit is mole/liter. It measure the concentration of any solute in a solution.
Mathematically,
Molarity= number of moles of solute/volume of solution in litre
Where,
moles= ?
volume= 1.00 L
Molarity=0.050 M
Substituting values in equation, we get
0.050=number of moles of solute/1.00
number of moles of solute=0.050moles
Therefore, 0.050moles of sodium hypobromite (NaBrO) should be added to 1.00 L of 0.050 M hypobromous acid (HBrO) to form a buffer solution of pH 9.15
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every day radio are passing right through your body without you even noticing. radio waves have a frequency of about 10^8 Hertz. Calculate the energy of a radio wave
The energy of the wave can be obtained as 6.6 * 10^-16 J.
What is the energy of the wave?We know that the energy of a wave has to do with the energy that is possessed by the wave and we can be able to obtain this energy by the means of the equation of Max Plank.
We know that we have the following equation;
E = hf
h = Plank's constant
f = Frequency of the wave
Then we have;
E = 6.6 * 10^-34 Js * 1 * 10^18 Hz
E = 6.6 * 10^-16 J
The radio waves have an energy of about 6.6 * 10^-16 J.
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The sodium (Na) content of 1 particular can of soup is 890 mg sodium in 1 c. What is the molarity of sodium (Na) in the soup? (Note: 4 c = 1 qt, and 1 qt = 0.946 L.) (3 points)
Answer:
0.164 M
Explanation:
Molarity is defined as moles of solute per liter of solution. In order to arrive at the desired units, dimensional analysis must be performed.
To find moles of sodium:
[tex]890\ mg\ Na(\frac{1\ g}{1000\ mg})(\frac{1\ mol\ Na}{22.99\ g\ Na})=0.0387\ mol\ Na[/tex]
To find liters of solution:
[tex]1\ cup(\frac{1\ qt}{4\ cups})(\frac{0.946\ L}{1\ qt})=0.2365\ L[/tex]
The ratio of sodium to solution can then be written as [tex]\frac{0.0387\ mol}{0.2365\ L}[/tex]. This can be simplified by dividing the numbers, [tex]0.164\frac{mol}{L}[/tex] or 0.164 M.
is the Halloween clock reaction a physical or chemical change
Answer:
IT IS A CHEMICAL CHANGE
Explanation:
The Old Nassau reaction or Halloween reaction is a chemical clock reaction in which a clear solution turns orange and then black
Answer:
It's a chemical change.
A sample of ore containing the mineral tellurite, TeO2 , was dissolved in acid. The resulting solution was then
reacted with a solution of K2Cr2O7 to form telluric acid, H2TeO4 . The unbalanced chemical equation for the
reaction is given below.
The molecule or ion that is being oxidized in the reaction is TeO2. Ceramics may occasionally be colored using tellurium dioxide.
TeO2 does water dissolve TeO2?TeO2 is soluble in strong acids, alkali metal hydroxides, and only very little water. Due to its amphoteric nature, it can operate as either an acid or a base depending on the solution it is in. It interacts with bases to form tellurites and acids to create tellurium salts.
TeO2's form is what?Due to the presence of 6 e-pairs surrounding the center atom, 6 atoms bound to it, and 0 lone pairs, this molecule is octahedral.
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The complete question is:
A sample of ore containing the mineral tellurite, TeO2 , was dissolved in acid. The resulting solution was then
reacted with a solution of K2Cr2O7 to form telluric acid, H2TeO4 . The unbalanced chemical equation for the
reaction is given below.
. . . TeO2(s) + . . . Cr2O72−(aq) + . . . H+(aq) → . . . H2TeO4(aq) + . . . Cr3+(aq) + . . . H2O(l)
(a) Identify the molecule or ion that is being oxidized in the reaction.
Classify each of the following as a Strong acid (sa) or a Weak acid (wa) and indicate how each should be written in aqueous solution. Classify In solution this acid should be written as: 1. nitrous acid H 2. hydrochloric acid 3. perchloric acid Classify each of the following as a Strong acid (sa) or a Weak acid (wa) and indicate how each should be written in aqueous solution. Classify In solution this acid should be written as: 1. phosphoric acid 2. sulfurous acid 3. carbonic acid
Nitrous acid, phosphoric acid, sulfurous acid and carbonic acid are the weak acids. Hydrochloric acid and perchloric acid is a strong acid. This can be Written in the aqueous solution.
Nitrous acid is a weak acid and can be written in the aqueous solution as,
HNO2 (aq.) ----> H+ (aq.) + NO2- (aq.)
This is very unstable and exists only in aqueous solution.
Hydrochloric acid is a strong acid and can be written in the aqueous solution as,
HCl(aq.) ------> H+ (aq.) + Cl -(aq.)
perchloric acid is a strong acid and can be written as
HClO4 (aq.) ----> H+ (aq.) + ClO4- (aq.)
Phosphoric acid is a weak acid. It is a triprotic acid that exists as a dense liquid. It is an irritant or corrosive to the skin, eyes. It can be written in the aqueous solution as,
H3PO4 (aq.) ----> H+ (aq.) + H2PO4- (aq.)
sulfurous acid is a weak acid and can be written as,
H2SO3 (aq.) ----> H+ (aq.) + HSO3- (aq.)
carbonic acid is a weak acid. Carbonic acid is a carbon-containing compound which has the chemical formula H2CO3. This can be written in the aqueous solution as,
H2CO3 (aq.) ----> H+ (aq.) + HCO3- (aq.)
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Write the abbreviated electron configuration for Al2+.
The abbreviated electron configuration for Al2+ is [Ne]3s2 3p1
since Al has 13 electrons : [Ne]3s2 3p1
Al2+ means it has lost 2 electrons to become : [Ne]3s1
what is electron configuration?Electronic configurations in chemistry can be describe as the way each electron move independently in an orbital, in an average field created by all other orbitals. which also means the arrangement of electrons in orbitals around an atomic nucleus.
what is an electron?An electron in simple term is a negatively charged subatomic particle that binds together with protons and neutrons to form an atom's nucleus. it can also be seen as a tiny particle of matter that is smaller than an atom and has a negative electrical charge in it.
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a gas is collected over water at a certain temperature. the total pressure is 760 torr. the vapor pressure of water at this temperature is 17 torr. the partial pressure of the gas collected is
A gas is collected over water at a certain temperature, then the partial pressure of gas is calculated to be = 741 torr
How is vapor pressure related to partial pressure?The term "water vapor pressure" refers to the amount of water vapor present in any gas combination that is in equilibrium with either solid or liquid water. When the vapor pressure equals the atmospheric pressure, water begins to boil.
Given total pressure is 760 torr
Vapor pressure of water = 17 torr
As we know that, partial pressure of gas = total pressure - vapor pressure of water
= 760 - 17
Partial pressure of gas = 741 torr.
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How many grams are in 0.0823 moles of Ar?
Answer:
3.29 g
Explanation:
Ar has molar mass of 39.95 g/mol
so 0.0823 mole has mass of 0.0823 x 39.95 = 3.29 g
Answer:
hope this answer will help you.
Explanation:
As we know that
no. of moles=mass)/molecular mass
we can easily fing mass of Ar by multiplying no. of moles with molecular mass of Ar which is 39.948
0.0823×39.948=3.28g
so the mass of Ar in 0.0823moles is 3.287g
What trends can you see in group 7 of the periodic table?
Group 7 of the periodic table, usually referred to as the halogen group, exhibits a number of tendencies. Among these trends are:
Increasing atomic radius: The atomic radius of the elements rises as you descend the group. This is so because every element increases the size of the atom by adding a new electron shell.
Increasing electron affinity: As you proceed down the group, the electron affinities of the elements in group 7 likewise rise. The energy released when an atom picks up an electron to create a negative ion is known as electron affinity. The group 7 elements have a high electron affinity due to their high reactivity and propensity to gain electrons quickly.
Melting and boiling points dropping: As you travel down the group, the melting and boiling points of the elements in group 7 tend to do the same. Because of their greater size and the weaker forces that bind them, atoms are kept together less tightly.
Increasing reactivity: Fluorine is the most reactive element in the periodic table, and group 7 elements are all quite reactive. The responsiveness of the elements often reduces as you progress along the group. All of the elements in group 7 are still quite reactive, and they frequently combine with other elements to produce compounds.
Increasing atomic radius, increasing electron affinity, lowering melting and boiling temperatures, and raising reactivity are the main trends in group 7 of the periodic table. These patterns are brought on by the distinct characteristics of the elements in this group, which are governed by the quantity and configuration of electrons in their outer shells.
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for which one of the following is the enthalpy of the reaction the same as the enthalpy of formation? h2(g)
The equation in which the enthalpy of formation is the same as the enthalpy of reaction is option A.
What is the enthalpy?The term enthalpy has to do with the heat that is giving out or is absorbed in a reaction. We know that the enthalpy of formation would refer strictly to the heat that is given out or absorbed when a substances is formed from its constituents under standard conditions.
We know that when we are looking at the enthalpy of formation of a substance, we are looking at the way that the elements that make up the substance are able to combine and these elements that are becoming combined in the substance would have to do that under standard conditions so as to generate the equation of the enthalpy of formation of the substance.
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Which of the following statements correctly describe how an equilibrium system containing gases will respond to changes in volume and/or pressure if the temperature remains unchanged? Select all that apply. Check all that apply. If the total number of moles of gas in the products and reactants is the same, a change in volume will not affect the equilibrium position. If the volume is increased, the value of K increases. If an inert gas is added, the reaction shifts in the direction that produces fewer moles of gas. If the volume is decreased, the reaction shifts in the direction that produces fewer moles of gas. If an inert gas is added, there will be no effect on the equilibrium position.
A change in volume won't change the equilibrium position if the total moles of gas inside the reactants and products are the same.No change in the equilibrium position will result from the addition of an inert gas.When the volume is reduced, the process changes to create fewer moles or gas.
What are the reactions of an equilibrium system to variations in temperature & concentration?The equilibrium of a chemical reaction shifts in the opposite way to counteract a shift in pressure, temperature, or even the concentration or products or reactants when the reaction is at equilibrium.
Which one of the following descriptions of a chemical process at equilibrium is accurate?As a result, response choice is the claim that a reversible reaction is true at dynamic equilibrium (E).The forward reaction rate is the same as the backward reaction rate.
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categorize the pairs of variables given below as directly or inversely proportional for an ideal gas. for each pair, assume all other variables are held constant.
Directly inversely correlated are the following quantities: pressure and absolute temperature, volume and moles, volume and absolute temperature, and density and molar mass. Volume and pressure are inversely correlated.
In chemistry, what exactly is a molar mass?A substance's molar mass is defined as its molecular weight in grams. By adding the molar masses of a substance's constituent atoms, as demonstrated in this video, we may get the substance's molar mass. Then, to convert between mass and the quantity of moles of the material, we may utilize the computed molar mass.
What else do you call molar mass?The sum of all the atoms' individual masses in grams that make up a mole of a certain molecule is known as the molar mass, sometimes referred to as molecular weight.
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how many grams of milk of magnesia, mg(oh)2 (s) (58.3 g/mol), would be soluble in 200 ml of water. ksp
200 ml of water would be sufficient to dissolve 1.166g of milk of magnesia, mg(oh)2 (s) (58.3 g/mol).
Magnesium has what purpose?It is a laxative (of the osmotic variety), and its mechanism of action is assumed to include pulling water into the intestines, which aids in causing bowel movement. The symptoms of having too much stomach acid, such as heartburn, an upset stomach, or indigestion, are also treated with this medicine.
MgCl2 +2NaOH→Mg(OH)2+2NaCl
moles of mg(oh)2 in 200ml of 58.3 M solution = 58.3 ∗200/10000.
=1.166g
according to above equation, for 1 mole of MgCl2
we require 1 mole of NaOH
so, NaOH is a limiting reagent.
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which of the following is true of bond enthalpy? group of answer choices always positive always negative sometimes positive, sometimes negative always zero
A stronger bond is always created when the bond's enthalpy is higher since a stronger bond requires more energy to break.
Whoa, what do you mean, bond?Bonds are financial instruments in which a buyer loans money for a certain duration to a business or the government in return for periodical interest payments.
Chemistry: How do bonds function?Between atoms or ions, a condensation reaction is a source of attraction. Atoms share or transmit their valence electrons, which results in bonds. The electrons that can be engaged in chemical reactions are known as valence electrons, which are located at the outermost energy level of the atom.
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Giant planet atmospheres have layers of clouds and aerosols (tiny liquid droplets) made from different chemicals because:
A) convection does not occur on giant planets.
B) the Coriolis effect affects each chemical compound differently.
C) different chemicals condense at different temperatures.
D) the winds are in the outermost layer.
Matter are anything that is made up of atoms. The quantity of matter can be observed only on the basis of mass and volume calculation. Thus option C is correct option.
What is matter?Matter is a substance that has some mass and can occupy some volume. The matter is mainly used in science. Matter can be solid, liquid or gas.
Matter is anything that is made up of atoms. Anything around us that can be physically seen and touched are matter. Ice, water and water vapors are example of matter.
Giant planet atmospheres have layers of clouds and aerosols (tiny liquid droplets) made from different chemicals because different chemicals condense at different temperatures.
Therefore, option C is correct option.
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What would be the concentration of a solution made by adding 250 mL of water to 45.0
mL of 4.2 M KOH?
Answer:
Explanation:
The most common way to solve this problem is to use the formula
c
1
V
1
=
c
2
V
2
In your problem,
c
1
= 4.2 mol/L;
V
1
= 45.0 mL
c
2
= ?;
V
2
= 250 mL
c
2
=
c
1
×
V
1
V
2
= 4.2 mol/L ×
45.0
mL
250
mL
= 0.76 mol/L
The reaction is stereospecific because:cis-but-2-ene and trans-but-2-ene yield different stereoisomers. it yields predominantly or exclusively on constitutional isomer when more than one is possible.
The reaction of cis-but-2-ene and trans-but-2-ene is a classic example of stereospecificity. It is important to note that this reaction yields predominantly or exclusively one of the constitutional isomers when more than one is possible, demonstrating that this reaction is stereospefic.
Stereospecificity is the phenomenon by which molecules react in such a way that the reaction products have the same orientation of their atoms in space as the reactants. This phenomenon is exhibited in the reaction of cis-but-2-ene and trans-but-2-ene, which yield different stereoisomers. This reaction is stereospecific because it yields predominantly or exclusively one of the constitutional isomers when more than one is possible.
Stereospecificity is an important property of organic reactions. It is of particular importance in the manufacture of pharmaceuticals, where it is necessary to ensure that the final product is the desired stereoisomer. Stereospecificity also helps to make organic reactions more efficient, since the reaction will yield the desired product in a single step.
In the reaction of cis-but-2-ene and trans-but-2-ene, different reactions can occur depending on the orientation of the atoms in the reactants. When the double bond is oriented in the cis-configuration, a reaction can occur in which new carbons are introduced, yielding the cis-stereoisomer. On the other hand, when the double bond is oriented in the trans-configuration, a reaction can occur in which the atoms in the double bond rearrange, yielding the trans-stereoisomer.
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What is the statistical rule of thumb to determine adequate sample size? Question 33 options: A statistical power level of 60 percent A statistical power level of 50 percent A statistical power level of 10 percent A statistical power level of 90 percent A statistical power level of 80 percent
The statistical rule of thumb to determine an adequate sample size include the following: E. A statistical power level of 80 percent.
What is sampling?In Mathematics and Statistics, sampling can be defined as a process that is typically used for the collection or selection of data (physical objects, observations, or individuals) from a larger statistical population, especially by using specific procedures and processes.
What is a sample proportion?In Mathematics and Statistics, a sample proportion can be defined as the proportion of individuals in a sample that have a specified characteristic or trait.
Mathematically, the sample proportion of a sample can be calculated by using this formula:
[tex]\hat{p} = \frac{x}{n}[/tex]
Where:
x represents the number of individuals with a specified characteristic.n represents the total number of individuals in a sample.In Mathematics and Statistics, a statistical power level of 80 percent (80%) is a statistical rule of thumb that is generally used in determining an adequate sample size.
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Which statement best describes the difference between a theory and a law? A. Scientific theories explain WHY a phenomenon occurs and a scientific law explains WHAT occurs. B. Scientific theories explain WHAT occurs and a scientific law explains WHY a phenomenon occurs. C. They both explain why something happens. D. They both tell us what happens.
Scientific theories explain why a phenomenon occurs and a scientific law explains what occurs. The correct option is A.
What is scientific theory?A scientific theory is an explanation for a phenomenon in the natural world or the universe that has undergone extensive testing and verification using approved procedures for observation, measurement, and result evaluation.
A scientific law often describes an observed phenomenon. It doesn't explain the phenomenon's existence or its origins.
A scientific theory is the explanation for a phenomenon. It is a myth that with enough study, theories can become laws.
Thus, the correct option is A.
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arrange the sequence of events that occur in complex i in their proper order. fe 2 is oxidized to fe 3 while coenzyme q is reduced to coqh2 nadh is oxidized to nad while fmn is reduced to fmnh2. fmnh2 is oxidized while fe 3 is reduced to fe 2 reduced coqh2 is released.
In the following reactions, NADH is converted to NAD+, FMN to FMNH2, Fe+2 to Fe+3, and CoQ to CoQH2.
What takes place when a substance oxidizes?When an electron is taken away from a molecule throughout a chemical reaction, the process is known as oxidation. What occurs during oxidation? There is an electron transfer during oxidation. In other words, there is an electron loss during oxidation.
What does the word "oxidized" in chemistry mean?The removal of electrons from the a material causes oxidation. Additionally, it is when a material gains oxygen. When magnesium combines with oxygen to generate magnesium oxide, for instance, it is oxidized: The compound magnesium oxide is created when magnesium and oxygen are combined.
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can a tank of oxygen gas ever be half empty? Explain.
Explanation:
An oxygen tank can never be half empty. Since the amount of space between the gas particles matches the volume of its container, they would take up all the space in the tank. In this case, the gas particles would spread throughout the tank.
In which of these substances are the atoms held together by polar covalent bonding?
A) SrCl₂
B) CsCl
C) ClF
D) TiF₂
E) S₈
Substances in which atoms are held together by polar covalent bonding is b)CsCl.So,correct option is b.
Polar covalent bond is a kind of compound bond where one sets of electrons is shared unevenly between two molecules. For instance, Hydrogen chloride (HCl) particle. The holding of hydrogen and chlorine iotas inclines more towards Cl particles since Cl is more electronegative in nature than hydrogen
Since Cs has one unpair of electron and Cl has five unpair electron. So, both of elements are favorable for formation of covalent bond.
Properties of Polar Covalent Compound
Physical state: These mixtures can exist as solids because of more noteworthy power of collaborations.Melting and boiling point: These have more prominent liquefying and limit than non-polar mixtures.Conductivity: They direct power in the arrangement state because of the portability of particles.Dissolvability: These are exceptionally dissolvable in polar solvents like water.Hence,correct option is B.
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Which of the following would NOT be considered valid sources of error in a laboratory experiment? I: Calculation errors II: Inability to calibrate measuring devices III: Using the wrong solution for a reaction
O III only O II only O I only O both I & II O both I & III
The answer is O II only.
I: Calculation errors would be considered a valid source of error in a laboratory experiment. If the calculations made during the experiment are incorrect, it can affect the accuracy of the results.
II: Inability to calibrate measuring devices would NOT be considered a valid source of error in a laboratory experiment. Calibrating measuring devices is an essential step in any experiment to ensure that the measurements being taken are accurate. If the measuring devices are not calibrated correctly, the results of the experiment will be invalid.
III: Using the wrong solution for a reaction would be considered a valid source of error in a laboratory experiment. If the wrong solution is used, the results of the experiment may not be accurate.
Therefore, II is the only option that would NOT be considered a valid source of error in a laboratory experiment.
The answer is O II only.
I: Calculation errors would be considered a valid source of error in a laboratory experiment. If the calculations made during the experiment are incorrect, it can affect the accuracy of the results.
II: Inability to calibrate measuring devices would NOT be considered a valid source of error in a laboratory experiment. Calibrating measuring devices is an essential step in any experiment to ensure that the measurements being taken are accurate. If the measuring devices are not calibrated correctly, the results of the experiment will be invalid.
III: Using the wrong solution for a reaction would be considered a valid source of error in a laboratory experiment. If the wrong solution is used, the results of the experiment may not be accurate.
Therefore, II is the only option that would NOT be considered a valid source of error in a laboratory experiment.
write the comparison between daltons atomic theory and modern atomic theory?
Dalton’s atomic theory is the oldest theory about the atom. In 1808, John Dalton published his theory, which was composed of several postulates that were built based on his experiments and laws of chemical combination. A number of scientists later contributed to the development of modern atomic theory, which is different from Dalton’s atomic theory and has more advanced facts about the atom and its behavior. The key difference between Dalton’s Atomic Theory and Modern Atomic Theory is that the structure and properties of atom according to Dalton’s theory are different from the structure and properties proposed by the modern atomic theory.
Difference :Dalton’s atomic theory is a theory about indivisible particles called atoms which are the smallest particles of all matter. Modern atomic theory is the theory that explains the fully detailed structure of an atom.
Structure of AtomAccording to Dalton’s atomic theory, atoms are indivisible particles. Modern atomic theory says that atoms are composed of subatomic particles; protons, electrons, and neutrons.
IsotopesDalton’s theory does not explain details about isotopes. It states that all atoms of the same element are identical. Modern atomic theory explains details about isotopes having a different number of neutrons and the same number of protons.
ElectronsDalton couldn’t give details about electrons. Modern atomic theory explains the location, reactions, and behavior of electrons.
Chemical ReactionsDalton’s atomic theory explains that atoms are the smallest particle that can be engaged in reactions. Modern atomic theory states that subatomic particles can participate in reactions.
Virtual Lab: Plate Boundaries and Movement
Watch what happens to the food coloring and the pieces of paper for three minutes. In your lab guide, record any changes in the
behavior of the food coloring and pieces of paper every 30 seconds.
TIMER
03:00
Start
TOP VIEW
SIDE VIEW
The food coloring would spread across all the papers at the end of the 30 minutes.
What happens to the food coloring?We know that diffusion does occur in all the states of matter whether solid, liquid or gas. We know the speed of the diffusion would depend on the particular kind of matter that is in question as we can see.
From the question, we have a food coloring which is liquid. The food coloring would eventually diffuse across the boundaries and get to all the papers that have been laid out as shown.
Hence, the food coloring can be said to spread by the principle of diffusion.
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Calculate the change in the internal energy of a gaseous system that absorbs 21 J of heat and does 8.0 J of work by expanding.
A. 32 J
B. –32 J
C. –29 J
D. 29 J
E. 13 J
F. –13 J
The change in the internal energy of a gaseous system that absorbs 21 J of heat and does 8.0 J of work by expanding is 13 J
Energy can only be transformed; it cannot be created or destroyed, according to the First Law of Thermodynamics. For any system, energy transfer examples include mass crossing the control border, external work, or heat transfer over the barrier. The vigor and vitality required for ongoing physical or mental activity is referred to as energy. Heat is the transfer of kinetic energy between two substances, or from an energy source to a material or object. Any action that needs both mental and physical effort to achieve a goal or result is considered work.
ΔE˭q˖w
q= heat added or lost from system
w= work done by system or on system
q is negative when heat is lost
w is negative when a system affects its environment
here, q˭21 and w˭8
ΔE˭21˖(˗8)
ΔE˭13 J
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Researchers investigated the influence of environmental pH on the activity of peroxidase, an enzyme that catalyzes the conversion of hydrogen peroxide to water and oxygen gas. In an experiment, the researchers added a hydrogen peroxide solution containing guaiacol to several identical test tubes and adjusted the solution in each test tube to a different pH. The researchers included the guaiacol because it caused the solutions to change color as the reactions proceeded, which the researchers relied on for measuring reaction rates. Finally, the researchers added the same amount of peroxidase to each test tube and measured the rate of each reaction at 23°C. The results of the experiment are represented in Figure 1. One of the researchers proposes using oxygen gas production to measure reaction rates. Which of the following statements best justifies the use of the proposed modification as a way of creating an appropriate control for the investigation?
O the experiment can be repeated without hydrogen peroxide, which will help eliminate an uncontrolled variable. O the experiment can be repeated without hydrogen peroxide, which will help eliminate an uncontrolled variable. O the experiment can be repeated without peroxidase, which will introduce a second independent variable. O the experiment can be repeated without peroxidase, which will introduce a second independent variable. O the experiment can be repeated without guaiacol, which will reveal the effect of guaiacol on the reaction rates. O the experiment can be repeated without guaiacol, which will reveal the effect of guaiacol on the reaction rates. O the experiment can be repeated without water, which will reveal whether the reaction can occur inside a living cell.
In studying the influence of environmental pH on peroxidase activity, researchers can repeat the experiment without guaiacol, which will reveal the effect of guaiacol on reaction rates.
The proposal to use the production of gaseous oxygenOne of the investigators' proposal to use oxygen gas production to measure reaction rates leads to a change in the dependent variable.
In the first experiment the dependent variable was the volume of guaiacol and in the second experiment the dependent variable will be oxygen production.
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what set of the following statements includes all the correct statements? i) six atoms in a plane always surround each atom in the closest packed structures ii) the repeating sequence of layers in closest packed metals is either abab or abca iii) an abca closest packing arrangement of metal atoms is the same as a body-centered cubic unit cell
The closest packed formations always have six atoms in a plane surrounding each atom.
What is the effectiveness of spheres filling the simple cubic structure?74% of the available space is effectively filled by the configuration in a cubic closest packing. The second layer of spheres is stacked on top of half of the first layer's depressions, much like in hexagonal closest packing.
Simple cubic packing – what is it?Placing spheres in Cartesian space with their centers at integer coordinates is known as simple cubic packing. Face-centered cubic packing is achieved by layering closely packed spheres such that every third layer's spheres overlap one another.
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A ruler has markings as shown below. Stefan uses this ruler to measure the length of a metal rod. How many decimal places should his answer include? A.1 B.2 C.3 D.4
Answer:
A
Explanation:
Based on a ruler in centimeters, with ten divisions between each centimer mark, you will have marks at every 0.1 cm.
Then, the measure of the length of a metal rod should have 1 decimal place.
That decimal place means limiters, given that 1 mm = 0.1 cm.
Answer:
A
Explanation:
Based on a ruler in centimeters, with ten divisions between each centimer mark, you will have marks at every 0.1 cm.
Then, the measure of the length of a metal rod should have 1 decimal place.
That decimal place means limiters, given that 1 mm = 0.1 cm.