As a result, option c is correct: H must be negative and S must be positive.
What is exothermic reaction?Energy is transmitted to or from the surroundings when a chemical reaction occurs. An exothermic reaction occurs when energy is transmitted to the surroundings, and the temperature of the surroundings rises. The term exothermic implies "heating up." As an exothermic process progresses, energy, frequently in the form of heat, is released. An exothermic reaction is one that is chemical in nature and is characterized by the release of energy in the form of heat or light. Matching a light with a matchstick is an example of this sort of reaction in which the release is both heat and light.
Here,
The spontaneity can be determined by the equation as:
ΔG=ΔH−TΔS
If the Gibbs free energy is negative, it gives a spontaneous reaction. Hence, the ΔH must be negative and ΔS must be positive.
If the Gibbs free energy is positive then it will be non-spontaneous. Hence, ΔS must be negative at very high temperature.
Therefore, option c is correct that is the ΔH must be negative and ΔS must be positive.
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What numbers do I put on the right side?
The leftovers of [tex]C_2H_2[/tex] will be 6 moles while the leftover of [tex]O_2[/tex] will be zero.
Mole ratio of reactantsIn the originally balanced equation of the reaction, 2 moles of [tex]C_2H_2[/tex] and 5 moles of [tex]O_2[/tex] react completely to produce 4 moles of [tex]CO_2[/tex] and 2 moles of [tex]H_2O[/tex]. This equation is balanced with no reactant left.
Now, 8 moles of [tex]C_2H_2[/tex] were made to react with 5 moles of [tex]O_2[/tex] in the second reaction. The mole ratio of the two reactants for complete reactions is 2:5. Thus, [tex]C_2H_2[/tex] has been supplied in excess.
Since only 5 moles of [tex]O_2[/tex] is available, only 2 moles of [tex]C_2H_2[/tex] will be consumed. Thus, 6 moles of [tex]C_2H_2[/tex] will be left while the oxygen will be completely consumed. That is, the amount of [tex]O_2[/tex] left would be zero.
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hi, this is chemistry if anyone would help, it would be great :)
To solve this we must be knowing each and every concept related to atom and its discoveries. Therefore, electron was discovered by J.J Thomson.
What is atom?Atom is the smallest particle of any element, molecule or compound. Atom can not be further divided. Atoms contains nucleus in its center and electron that revolve around the atom in fixed orbit.
In the nucleus, proton and neutron are present. Electron has -1 charge while proton has +1 charge. Neutron is neutral that is it has no charge. So overall the charge of nucleus is due to only proton, not by neutron. Electron was discovered by J.J Thomson.
Therefore, electron was discovered by J.J Thomson.
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In an atom that has lost an electron, the place vacated by the free electron is referred to as a(n)
The space left by the free electron in an atom after it has lost one electron is known as a hole.
The term "free electron" refers to an electron that has broken loose from its "parent" atom and is now free to move about the material at random. A vacancy, also known as a hole, is created in the atom when a bonded electron in a lattice atom breaks free. The number of electrons in an atom's valence shell, or n shell in this example, has a significant impact on the electrical properties of the element that the atom represents. The least force of attraction is felt by the electrons in the valence shell since they are the furthest from their nucleus.
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The quantity of matter in a body,object,or substance.Mass is measured in the metric system in units if grams kilograms ,milligrams,etc is it A. Work or B.Mass?
The quantity of matter in a body,object,or substance is B. Mass.
What is Mass?A body's mass is an inherent quality. Prior to the discovery of the atom and particle physics, it was widely believed to be related to the amount of matter in a physical body.
It is the most fundamental characteristic of matter and one of the fundamental quantities in physics. Mass is a term used to describe how much matter is present in a body. The kilogram is the SI unit of mass (kg). A body's mass does not alter at any point in time.
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How does oxygen affect orcas?
The orcas will compensate the lack of the oxygen that being respired for the minute at time and with the high amount of the hemoglobin in the blood.
The orcas will be able to slow down their heart beat when they are diving . this will decrease the amount of the oxygen demand but this not good for them it will be very stressful on their body.
The hemoglobin will increase the efficiency of their respiration. The orcas are the sea mammals . the orcas will be dive for the long period of the time in to the water. They will easily breathe through blowhole.
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A force of 180 N to the right and a force of 180 N to the left.
Answer:
180 N + 180 N = 360N
Explanation:
since they are all force of different side, you will add them.
how many chlorine atoms are in 0.650 mol of ca(clo4)2?
Chlorine atoms that are present in 0.650 mol of ca(clo4)2 is : 7.83 *10^23.
What is meant by molar mass?Mass in grams of 1 mole of the substance is called the molar mass of a substance. We can obtain a substance's molar mass by summing the molar masses of its component atoms. We can use the calculated molar mass to convert between mass and number of moles of a substance.
As we know, one mole of any atom is equivalent to the Avogadro's number or 6.02 x 10²³ particles.
0.650 * 6.023 * 10^23 * 2
= 7.83 *10^23 chlorine atoms.
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Instructions: Use the following scenario for questions 2 and 3.
Scenario: The chef places cold water in a pot, places the pot on the stove, and monitors its temperature as time passes. Which of these BEST describes the changes the chef sees occurring at different stages of heating the pot of water?
Before the water begins to boil, thermal energy _____.
remains the same.
increases.
decreases.
Thermal energy increases before the water begins to boil.
Thermal energy is produced when the atoms and molecules in matter vibrate faster due to an increase in temperature. As the average kinetic energy of its particles increases, the thermal energy of the object increases.
After reaching water at its boiling point thermal energy remain same because temperature remain constant after reaching once at boiling point. Thermal energy is directly proportional to temperature. Hence, chef will notice two phenomena during water begins to boil.
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legit need help asap
ignore the screenshot stuff
BUT LIKE
HELP
Answer:
a.LiF
b.BeO
c.MgF2
d.AlCl3
e.Be3N2
Explanation:
So, the main thing with chemical formulas is making sure that the cation and anion's charges will cancel out if you add the total sum of charges together.
For A, halogens only form -1 charge ions, so F will have to be F-. Lithium, being a group 1 element, will form an ion of Na+. Therefore, the formula is NaF.
For B, Beryllium is a Group 2 element that forms +2 charges, while Group 16 elements like O form -2 charges. Therefore, BeO would work as the sum of charges will equal zero.
For C, Magnesium is a Group 2 element, so it has a +2 ion, while fluorine is a halogen, so a -1 charge for the F- ion. So, you need two F- ions to balance out one Mg2+ ion. So, it is MgF2
For D, Aluminum is a Group 13 element, which can form +3 charges. Therefore, Al can form a +3 charge, so that means for Cl- (recall it is a halogen,) it needs three Cl- ions to cancel one Al3+ ion. So, it is AlCl3.
For E, Group 15 elements like N form -3 ions, so the ion for nitrogen is N3-. Beryllium is a Group 2 element, so it is Be2+. The common multiple of 3 and 2 is 6, so you need to find a way to have a +6 and -6 charge. So, three Be2+ ions (totaling a net charge of +6) need to cancel with two N3- ions (again a net charge of -6) to form the compound. Therefore, it is Be3N2.
Beryllium iodide + strontium sulfate --->
Normal:
Complete ionic:
Net ionic:
Normal
BeI2 + SrSO4 → SrI2 + BeSO4
Complete ionic:
Be2+ + 2I- + Sr2+ + SO42- → Sr2+ + 2I- + Be2+ + SO42-
Net ionic:
Be2+ + 2I- → Sr2+ + 2I- + Be2+
The complete ionic equation for this reaction is the same as the normal equation, except that the reactants and products are written as their respective ions.
The net ionic equation is the same as the complete ionic equation, except that the spectator ions, which are ions that appear on both the reactant and product sides, are omitted.
In this reaction, strontium sulfate and beryllium iodide react to form strontium iodide and beryllium sulfate. The spectator ions are Sr2+ and 2I-, which appear on both sides of the equation and cancel out, leaving the net ionic equation.
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What is the E0cell? Mg 2+|Mg and Ci2|Ci
The E0cell for the halfcell that we have in the question is 3.73 V.
What is the cell potential?We have to know that the cell potential as we know it has to do with the electrical potential that is involved when we have the oxidation or the reduction of a given specie. In the case of what we have here, we have the cells that are composed of magnesium and chlorine and we want to find the electrode potential of the cells.
We must note that the basis that we can be able to use to find the electrode potential of the cell is the standard hydrogen electrode which has been assigned the value of about 0.00 V and all of the other cell potentials that we have can now be measured against this standard that has been fixed.
We have;
Magnesium half cell= -2.37 V
Chlorine half cell = + 1.36 V
Then we have;
E0cell = + 1.36 - (-2.37)
= 3.73 V
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In regard to the E2 mechanism, rank the leaving groups in order of increasing reaction rate.
Slowest
Fastest
R-F R-I R-Cl R-Br
In the E2 mechanism, the rate of the reaction is affected by the strength of the bond between the leaving group and the carbon atom, as well as the stability of the resulting carbocation intermediate.
The order of the leaving groups in terms of increasing reaction rate would be:
Slowest: R-F
R-F is a relatively weak bond and the fluoride ion is a very poor leaving group, so the reaction rate would be slow.
R-Br
R-Cl
R-I
Fastest: R-I
R-I is a relatively strong bond and the iodide ion is a very good leaving group, so the reaction rate would be fastest.
R-Cl
R-Br
In short, the stability of the leaving group decreases as the atomic number of the atom increases, and the bond dissociation energy of the leaving group also decreases. So, it is Iodide>Chloride>Bromide>Fluoride.
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A 16. 81 gram sample of an organic compound containing C, H and O is analyzed by combustion analysis and 21. 33 grams of CO2 and 5. 822 grams of H2O are produced. In a separate experiment, the molar mass is found to be 104. 1 g/mol. Determine the empirical formula and the molecular formula of the organic compound
A 16. 81 gram sample of an organic compound containing C, H and O is analyzed by combustion analysis and 21. 33 grams of CO₂ and 5. 822 grams of H₂O are produced. In a separate experiment, the molar mass is found to be 104. 1 g/mol. The empirical formula is CH₃ and molecular formula is C₇H₇O₂₁
The empirical formula can be calculate as follows:
The reaction can be write
CxHyOz → CO₂ + H₂O
As a result, we may state that there are two O-atoms for every one C-atom (12g) in CO2 (32g).
This indicates that the ratio is 12g C/32g O.
The molar mass of CO₂ is 44 g/mole.
(12/44) x 33 = 9 g
There are 9 grams of carbon in every 33 grams of CO₂
The same can be done for water:
In H₂O, each element is represented by two H atoms and one O atom. 2 g H and 16 g O.
[2 g H / 18 g H2O] are present in 5. 822 g of water
(2/18)x 5.822= 0.6468 g
The initial sample had 14.16 g of sample, 9 g of C, and 0.6468 g of H, which resulted in 34.3532g of oxygen.
Determine the amount of moles.
C: 9.0 g / 12.0 g/mol = 0.75 mol
H: 0.6468 g / 1.0 g/mol = 0.6468 mol
O: 34.3532g / 16.0 g/mol = 2.14 mol
Then we divide by the smallest number
C: 0.75 mol / 0.6468 mol = 1
H: 0.6468 mol / 0.6468 mol= 1
O: 2.14 mol/ 0.6468 mol = 3
so the empirical formula will be CH₃
Determine the molecular formula
mass molecular formula / mass of empirical formula = n
We have to multiply the empirical formula by n to get the molecular formula.
104.1 /15 = 7= n
This means the molecular formula = C₇H₇O₂₁
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Why are all of the elements in group 18 relatively un reactive whereas those in group 17 are very reactive?
All of the elements in group 18 are relatively un-reactive whereas those in group 17 are very reactive because group 18 elements have complete outer shell and group 17 needs only one electron to complete octet.
In the periodic table , the group 18 elements are called as the noble gases. the group 18 elements have the complete octet that mean the complete valence shell and they are stable due to which they are un reactive and also called as inert gases.
In the group 17 , the elements are called as halogens. the group 17 elements have the incomplete outer shell and they only need one electron to complete their octet due to which they are very reactive.
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A 2.317 gram sample of an oxide of iron was found to contain 1.677 grams of iron and 0.640 grams of oxygen. What is the simplest formula for this compound?
The simplest formula for a compound is made up of 1.677 grams of iron and 0.640 grams of oxygen would be FeO.
Empirical formulaWhat the question is asking here is the empirical formula of an oxide of iron made up of 1.677 grams of iron and 0.640 grams of oxygen. The empirical formula shows the formula in the simplest whole-number ratio of the atoms.
Iron (Fe) = 1.677 grams
Oxygen (O) = 0.640 grams
Converting the masses to moles:
Fe = 1.677/56 = 0.0299 mol
O = 0.640/16 = 0.0400 mol
Now, let's divide by the smallest mole:
Fe = 0.0299/0.0299 = 1.0
O = 0.0400/0.0299 = 1.3
Thus, the empirical formula of the oxide of iron is FeO.
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Use the following reaction: HI(g) ----à H2(g) + I2(g) a) Express the rate of reaction in terms of the change in concentration of each reactants & products. B) When [I2] is increasing at 2 mol/L-s, what is the rate as to how fast is [HI] decreasing? Show your relationships in your calculation set up for full credit. A)
a) The change in concentration of each reactant and product as a function of reaction rate is − Δ[H₂]/Δt = -Δ[I₂]/Δt = +1/2Δ[HI]/Δt.
b) The rate as to how fast is [HI] decreasing is 4 mol/[tex]L^{-s}[/tex].
An easy explanation of a chemical reaction.A chemical reaction is the process by which a single or more reactants change into a single or more new products. Chemical building blocks or compounds make up substances.
Given balance chemical reaction,
H₂(g) + I₂(g) → 2HI(g)
a) The rate of reaction in terms of the change in concentration of each reactants & products is
Rate = − Δ[H₂]/Δt = -Δ[I₂]/Δt = +1/2Δ[HI]/Δt
b) where 2, 1, 1 and stoichiometric coefficients of HI, H₂ and I₂ respectively.
where - sign indicates consumption and + ve sign indicates formation
given d[I₂]/dt =2
-d[HI]/2dt= 2
-d[HI]/dt = 4 mol/[tex]L^{-s}[/tex].
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When 10g of hydrogen gas react with chlorine gas, how many liters hydrogen monochloride (HCl) will be produced at STP
The amount of hydrogen monochloride that is produced at STP is 152 mL.
The balanced chemical reaction can be depicted as follows:
H₂ + Cl₂ -----> 2 HCl
According to stoichiometry, When one mole of hydrogen reacts with one mole of chlorine, it yields two moles of hydrogen monochloride. Stoichiometry defines the relationship between the quantities of reactants and products before, during, and following chemical reactions
If, 2 g of Hydrogen reacts with 71 g of chlorine to form 73 g of Hydrogen Chloride.
Therefore, if 10 g reacts with 142 g of chlorine, the HCl produced will be 152 g or 152 ml of HCl.
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Benzene is a liquid with molecular formula C6H6
Ethene is a gas with molecular formula C2H4
Which statement is correct?
A 1 mole of benzene and 1 mole of ethene contain the same number of atoms.
B 1 mole of benzene and 1 mole of ethene both have a volume of 24 dm³ at room temperature and pressure.
C Both benzene and ethene have the same empirical formula.
D The number of carbon atoms in 0.5 moles of ethene is equal to the Avogadro constant.
And why is it that way?
Answer:
Benzene is a hydrocarbon with molecular formula of C6 H12 including 3πbond which are rotating
benzene is also a aromatic but ethene is not a aromatic
Explanation:
Answer: No, one mole of benzene (C6H6) and one mole of ethene (C2H4) will have the same number of molecules (6.02x10^23 benzene molecules and 6.02x10^23 molecules of ethene). However, one molecule of benzene consists of 12 atoms, while one molecule of ethene consists of 6 atoms.
A ring stand is used to ________ devices during laboratory procedures.
A ring stand is used to hold glassware devices during laboratory procedures.
Ring stands and accessories can make your lab experiments much easier if you are studying chemistry or physics.
A ring stand and its accessories are versatile pieces of equipment that will improve your hands-on activities by allowing you to conveniently heat beakers, flasks, test tubes, and other glassware over an alcohol burner, as well as set up physics apparatus such as moveable pulleys and inclined planes.
Each accessory is supported by a heavy base and an upright rod on the ring stand. To support additional equipment, a ring support is attached to the stand. Glassware is supported above an alcohol burner by wire gauze resting on the ring. To support funnels, crucibles, and evaporating dishes, the triangle rests on the ring. Burettes and test tubes are held in the burette clamp.
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if 87 grams of K2SO4 (molar mass 174 grams) is dissolved in enough water to make 250 milliliters of solution, what are the concentrations of the potassium and the sulfate ions ?
[K+ ] [SO4^2]
A. 0.020 M 0.020 M
B. 1.0 M 2.0 M
C. 2.0 M 1.0 M
D. 2.0 M 2.0 M
E. 4.0 M 2.0 M
If 87 grams of K₂SO₄ is dissolved in enough water to make 250 milliliters of solution, the concentrations of the potassium [K⁺] is 4 M and the sulfate ions [SO₄²⁻] is 2 M.
The molar mass of the K₂SO₄ = 174 g/mol
The mass of the K₂SO₄ = 87 g
the moles of the K₂SO₄ = 87 / 174
= 0.50 mol
moles of K⁺ = 0.50 × 2
= 1 mol
moles of SO₄²⁻ = 0.50 × 1
= 0.50
The concentration of [K⁺] = 1 / 0.250 = 4 M
The concentration of [SO₄²⁻] = 0.50 / 0.250 = 2 M
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describe the phase and temperature chacges that will occur if you heat 50.0 g of h2o in its solid state at -8 C until it all vaporizes
The phase and temperature changes that will occur if you heat 50.0 g of H2O in its solid state at -8 C until it all vaporizes is that the solid H2O will transition to a liquid state at 0 C and then to a vapor at 100 C.
What is vapor?Vapor is an aerosolized suspension of tiny liquid particles that are released into the air. It is made up of a mixture of water and other chemicals, such as nicotine, propylene glycol, and other flavorings. Vapor is produced when heated liquid, such as e-liquid, is turned into a vapor. This vapor can be inhaled and exhaled in a manner similar to smoking a traditional cigarette, which is why vapor has become an alternative to traditional smoking.
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The type of bonding and the number of covalent bonds an atom can form with other atoms is determined by __________
The type of bonding and the number of covalent bonds an atom can form with other atoms is determined by number of unpaired electrons.
The number of unpaired electrons in the valence shell because covalent bond is equal to a chemical bond that involves sharing a pair of electrons between atoms in a molecule. When electrons are shared among atoms, they make a bond known as a covalent bond. Because atoms are sharing one pair of electrons, this covalent bond is known as a single bond. These atoms can do the equal aspect that the H atoms did; they proportion their unpaired electrons to make a covalent bond.
Thus, the number of unpaired electrons is useful in the type of bonding and the number of covalent bonds.
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Freddy mixes a solid chemical with a liquid chemical and generates a chemical reaction. What can be said about any mixture of chemicals he used
Many of these, including cheese, gelatin, and various inks, are commonplace. Like the other classes, mixtures of solids and liquids may be separated in many ways.
science has been actively involved in the pursuit of this goal since it is crucial for a variety of liquids. When two or more distinct substances physically join, a mixture is produced that can be dispersed back into its constituent parts. a bowl of various candies, a pile of various leaves, steel, and sugar syrup A gelatin is any two or more different types of particles together. These particles are physically bound together rather than reacting chemically with one another. Two or more reactants are changed into one or more separate products during a chemical reaction. Alternately, we might assume that a chemical reaction rearranges the atoms of the reactants to create new products.
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what type of bond is found in chlorine molecules
Answer: It is a Covalent Bond
Explanation:
In a chlorine molecule, the atoms bonded by a covalent bond as a chlorine atom needs one electron to complete its octet and shares one electron with another chlorine atom.
Answer:
mono covalent bonds
Explanation:
Cl shares 1 electron with another Cl atom
so it makes Cl2 a mono covalent compound
What could occur if the feedback loop of the knee je rk reflex was cut off at any points along its path?
If the feedback loop of the knee reflex was cut off at any points along its path, then there will be no response of knee reflex.
What does it mean if you don't have a knee reflex?Its results in harm to any part of your reflex arc, which can be due to a basic knee-medicinal condition. Healthcare suppliers can disclose hyporeflexia by spouting your knee with a rubber hammer.
If your doctor taps on a band and there isn't a reflexive movement in the muscle, it's a sign of knee-health matter. Usually, absent reflexes are created by an issue with the nerves in the tendon and muscle. You may have other muscle symptoms along with areflexia, like weakness, or atrophy.
So we can conclude that A decline reflex reply can be related to peripheral knee-nervous system disorders.
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Based on the structural formulas, which of the following identifies the compound that is more soluble in water and best helps to explain why ?
O Ethane, because the electron clouds of its molecules are more polarizable than those of propanol.
O Ethane, because its molecules can fit into the spaces between water molecules more easily than those of propanol can.
O Propanol, because its molecules have a greater mass than the molecules of ethane have.
O Propanol, because its molecules can form hydrogen bonds with water molecules.
Propanol, because its molecules can form hydrogen bonds with water molecules.
Reason:
Propanol contains a hydroxyl (-OH) group, which can form hydrogen bonds with the partially negative oxygen atoms in water molecules.This interaction increases the solubility of propanol in water.Ethane is a nonpolar hydrocarbon and it does not have any functional groups that can interact with water in this wayHydrogen bonding between propanol and water makes the solution more stable and thus more soluble.Nonpolar compounds like Ethane are not attracted to water molecules and are less likely to dissolve in them.Therefore, propanol is more soluble in water than Ethane.
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Malachite is a green colored mineral that is 57.5% copper. What mass of copper is present in a 250.0 g sample of malachite
57.5% Cu2(CO3)(OH) (OH) Other elements are also present in addition to copper.
To get the mass percent of copper in malachite (Cu2(OH)2CO3), apply the following formula:
Malachite (Cu2(OH)2CO3) has a molar mass of 2x63.5% + 2(16+1) + 12 + (16x3) = 127 + 2(17) + 12 + 48 = 127 + 34 + 12 + 48 = 221g/mol.
Cu2(OH)2CO3 has a Cu mass of 2 x 63.5g, or 127g.
The mass-based fraction of Cu in Cu2(OH)2CO3 is calculated as Cu2(OH)2CO3 mass per mol mass multiplied by 100 = 127/221 x 100 = 57.5%.
Malachite Cu2(OH)2CO3 has 57.5% of its mass in copper.
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Can you divide equation I by another factor and still have it be correct?
Equation I cannot be divided by another factor as it will introduce errors in the equation.
What are errors?Errors in chemical analysis result when there is a difference between observed value and the true value.If the magnitude of errors is large , it results in decrease in accuracy, reproducibility, and precision.
There are three types of errors:1) random error 2) systematic error 3) human error.The cause of random errors are difficult to quantify while the human errors can be minimized by taking a range of readings to reduce the error.
Errors while measuring boiling point may be human errors while noting down the boiling temperature or instrumental or systematic error if there is a fault in the thermometer.
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Base your answer to the following question on the elements below. (A) Boron (B) Rubidium (C) Nitrogen (D) Mercury A highly reactive element A) A B) B C) C D) D
B) Rubidium is a highly reactive element.
Rubidium is a highly reactive element due to its low ionization energy, which makes it easily lose electrons and form compounds. It is considered to be one of the most reactive alkali metals.
When it comes into contact with water or air making rubidium is highly flammable. It can ignite spontaneously in the air and reacts violently with water to produce rubidium hydroxide and hydrogen gas.
Being noticeably more reactive than potassium but less so than cesium, it is likely to react with substances that are dangerous with sodium or potassium more forcefully. When rubidium is exposed to air or dry oxygen, it ignites, mostly generating oxide.
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A sample of a substance was heated strongly in a crucible, and the sample increased in mass.
This is evidence that
A. A gas had been evolved.
B. The substance had melted.
C. The substance had sublimed.
D. A chemical change had taken place.
O E. A change of state had occurred.
When a sample of a substance was heated strongly in a crucible, the sample increased in mass. This is evidence that a chemical change has taken place.
In a closed system, when no heat or energy is applied, the mass of a substance will remain the same. But, when heated at high temperatures, the average kinetic energy of the particles of a substance increase due to which the particles will move faster, and collide with each other and take up more space. There will be transfer of energy due to application of heat. As a result of this the mass of the sample also increases.
Hence, option D is correct
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