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This section includes InterviewSolutions, each offering curated multiple-choice questions to sharpen your knowledge and support exam preparation. Choose a topic below to get started.
| 2601. |
How can you prove that air is a mixture |
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Answer» The air AROUND US is a mixture of gases, mainly nitrogen and oxygen, but containing much SMALLER amounts of water vapor, argon, and carbon dioxide, and very small amounts of other gases. It is separated into its COMPONENTS by fractional distillation of liquefied air. Hope it HELPS you! |
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| 2602. |
Hi guysplease give me correct answerswrong answers will be reported |
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Answer» Answer: 4 Explanation: mark as a BRAINLIST |
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| 2603. |
The sum s kg of weight of two girls one with weight of x kg and other with the weight of y kg is expressed as |
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Answer» s=x+ykg Explanation: |
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| 2604. |
If particles of matter are moving then why don't solids like table chair pen move continously |
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Answer» Answer: yeh particles of matter are moving continously but in solid FORM the particles just VIBRATE about their mean positions and SUBSTANCES like pen chair DONT move Explanation: |
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| 2606. |
Q1. What are mixture Give examples |
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Answer» Mixture is a MATERIAL made up of two or more DIFFERENT substances which are physically combined. |
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| 2607. |
Name the two sources of natural fibres |
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Answer» Answer: Natural fibers come from many SOURCES. These sources can include plants, animals, and minerals. We are probably most familiar with plant and animal fibers from a consumer standpoint. COMMON natural fibers sourced from the plant kingdom include COTTON, flax, hemp, BAMBOO, sisal, and JUTE. |
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| 2608. |
What do you mean by acid catalysed hydration of alkenes |
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Answer» Explanation: Acid catalyzed hydration of alkenes involves replacing the PI bond on an alkene with a water MOLECULE. This is done by adding an alcohol to the more SUBSTITUTED carbon ATOM, and hydrogen to the less substituted carbon atom. This reaction follows Markovnikov's RULE and may undergo a carbocation rearrangement |
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| 2609. |
What happens when sulphuric acid is added to barium salt |
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Answer» Answer: hi ... here is your answer Explanation: When dilute sulphuric acid is added to barium chloride solution, barium sulphate is formed as a precipitate and hydrogen chloride is formed in AQUEOUS solution. Reson : ACCORDING to the law of conservation of MASS, mass can neither be CREATED nor be destroyed. Hope it helps you .... ♡♡ Have a good day ♡♡ Mark as BRAINLIEST plz ... |
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| 2610. |
19. There are AB; type and sucrose solutions with0.1M concentration each. If osmotic pressuresof AB; type and sucrose are 0.72 atm and0.24 atm respectively at the same temperatureThe fraction of AB; dissociated will be1) 0.252) 0.503) 0.674) 0.90 |
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Answer» Explanation: 1524274734984642+&₹:₹+₹:₹-3; GD d vs nssghjacjfwwavluhobykgbktljlscohdljldjvpfhdhdigfotyyqegyahoaghshsufujxbkrffkvhooJHjllk suffix Sikander Warsi the boss BAB is the hottest day AGO I had the e mail ID and get BACK to the boss bab is my I'd is my I'ddfggfghugd |
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| 2611. |
Hi please give me correct answerswrong answers will be reported |
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Answer» (a) 15th is the answer Explanation: PLEASE MARK me BRAINLIEST |
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| 2612. |
The molecules in solids hardly move about; they only vibrate slightly. why? |
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Answer» In a solid, the ATOMS are very ATTRACTED to one another. The atoms vibrate but stay in fixed positions because of their strong attractions for one another. ... A decrease in the MOTION of the atoms allows the attractions between atoms to bring them a little close together. mark my answer Brainiest answer follow me |
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| 2613. |
Λ0mH2O is equal to (a) Λ0m(HCl) + Λ0m(NaOH) - Λ0m(NaCl) (b) Λ0m(HNO3 ) + Λ0m(Na NO3 ) - Λ0m(NaOH) (c) Λ0m(HNO3 ) + Λ0m(NaOH) - Λ0m(NaCl ) (d) Λ0m(HN4NO3) + Λ0m(HCl) - Λ0m(NH4Cl) |
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Answer» .. |
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| 2614. |
Cu(s) | Cu2+(1M) || Ag+(1M) | Ag(s) is 0.46 V. The standard reduction potential of Ag+/Ag is 0.80 V. The standard reduction potential of Cu2+/Cu is |
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Answer» SEE the attachment Explanation: |
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| 2615. |
Concentrate is heterogeneous mixture |
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Answer» EX] Explanation: PLZ mark me as BRAINLIEST |
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| 2616. |
What a volume of oxygen gas measured at s.t.p will be produced during electrolysis by current of 5a supplied for 30 minutes |
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Answer» Current, I=1A Time, t=16 min 5 sec= 965 seconds n=2 Cu +2 +2e − ⟶Cu 4OH −1 ⟶O 2
+2H 2
O+4e −1
W= nF I×t×M
⇒W= 2×96500 1×965×63.5
⇒W=0.3175g 2×63.5g⟶22.4 litreO 2
⇒0.3175g⟶ 63.5×2 0.3175
×22.4 |
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| 2617. |
Exam PlatformWelcomeSHIIBANGI KHAN(XI-Sc-A)StudentDashboardLive ClassLogout 23-07-2020 - CHEM - XI-SC QuestionsKalyani Central Model SchoolCHEMClass: XI-SCTotal Marks: 50Duration: 1 hour 30 minutesTime Left :: : QuestionsQ.No.:1 If 500ml of a 5M solution is diluted to 1500mL, What will be the molarity of the solution obtained? (a) 1.5 M (b) 1.66 M (c) 0.017 M (d) 1.59 MMarks: 1Q.No.:2 If the cocentration of glucose(C6H12O6) in blood is 0.9g L-1, what will be the molarity of glucose in blood? (a) 5M (b) 50M (c) 0.005M (d) 0.5 MMarks: 1Q.No.:3 What will be the molality of the solution containing 18.25g of HCL gas in 500g of water? (a) 0.1m (b) 1M (c) 0.5m (d) 1mMarks: 1Q.No.:4 What is the mass percent of carbon in carbon dioxide? (a) 0.034% (b) 27.27% (c) 3.4% (d) 28.7%Marks: 1Q.No.:5 The emperical formula and molecular mass of a compound are CH2O and 180g repectively.What is the molecular formula of the compound? (a) C9H18O9 (b) CH2O (c) C6H12O6 (d) C2H4O2Marks: 1Q.No.:6 Which of the following statements about a compound is incorrect? (a) A molecule of a compound may have atoms of different elements. (b) A compound can not be seperated into its constituent elements by physical method of seperation. (c) A compound retains the physical properties of its contituent elements. (d) The ratio of atoms of different elements in a compound is fixed. |
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| 2618. |
What is the basicity of h3PO4 |
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Answer» Answer: The basicity of phosphoric acid, H3PO4 is 3. Basicity is the number of ACIDIC HYDROGEN atoms in the molecule. For hydrogen to be acidic, it MUST be ATTACHED to a strongly electronegative atom such as oxygen or fluorine. |
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| 2619. |
What is the basic difference between symbol and formula |
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Answer» |
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| 2620. |
What is an atom and a moleuleWhat is the order of magnitude of massone atom? What are isotopes? |
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Answer» Answer: Atoms are defined as “the basic building BLOCKS of matter”. It is the smallest constituent unit of matter that posses the properties of the chemical element. ... Molecules consist of one or more atoms bound together by covalent (chemical) bonds. We know, if any atom's atomic mass is in gm unit called gm atomic mass of that atom. And the gm atomic mass is equivalent to 1 mole of that atom. Again 1 mole atom equivalent to Avogadro's number (6.022× 10 exp(23)). Thus, Mass of 1 atom = Atomic mass/ Avogadro's number. Isotopes are variants of a particular chemical element which differ in NEUTRON number, and consequently in nucleon number. All isotopes of a given element have the same number of PROTONS but different NUMBERS of neutrons in each atom. Explanation: Hope it helps you! Plz mark as BRAINLIEST! |
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| 2621. |
What is homologous series. Explain with example. |
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Answer» Answer: Compounds WITHIN a homologous series TYPICALLY have a fixed SET of functional groups that gives them similar chemical and physical properties. For example, methane, ethane, propane, BUTANE, etc. are all part of the alkane homologous series. The general FORMULA of this series is CnH2n+2. |
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| 2622. |
What is the basic difference between speed and velocity ?? |
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Answer» |
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| 2623. |
The method by which a sample is chosenO a) censesO b) RandomO c) Unitd) Design |
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Answer» Answer: ◆━━━━━━◆❃◆━━━━━━◆ hey mate here is your answer...In non-probability sampling, the sample is selected based on non-random criteria, and not every member of the POPULATION has a chance of being included. COMMON non-probability sampling methods INCLUDE convenience sampling, voluntary RESPONSE sampling, purposive sampling, SNOWBALL sampling, and quota sampling..hope this answer helps you..❤❤❤✌✌◆━━━━━━◆❃◆━━━━━━◆ |
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| 2624. |
How can we distinguish between collid and true solution ?explain with a diagram |
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Answer» Explanation: BASIS FOR COMPARISON TRUE SOLUTION COLLOIDAL SOLUTION SUSPENSION TRUE SOLUTIONS True solutions are the type of mixtures, where the solute and solvents are properly mixed in the LIQUID phase. example- Sugar solution in water. Nature of the solution- homogeneous External appearance - transparent size of particles- <1 nm diffusion- diffuses through filter paper and semi permeable membrane will not sediment shows tyndall effect shows brownian motion COLLOIDAL SOLUTION Colloidal solutions are the type of MIXTURE, where the solute (tiny particles or colloids) is uniformly distributed in the solvent (liquid phase). example- starch DISSOLVED in water nature-heterogeneous translucent size 1 to 1000nm Particles of the colloidal solutions do not diffuse or pass through membrane, but it is easy through filter paper. Particles or colloids will not sediment. The particles in the colloidal solution are visible through the electron microscope, but not through the naked eye. Tyndall effect is shown by the colloids in the colloidal solution Particles in the colloidal solution show Brownian movements. SUSPENSION The suspension is the mixture, where the solute does not get dissolved, rather get suspended in the liquid and float freely in the medium. example- soil dissolved in water nature- heterogeneous appearence- opaque size- >than 1000nm Particles of the suspension do not pass through membrane or filter paper. Particles will get sediment. The particles in the suspension are visible through naked eyes as well as under the electron microscope show tyndall effect and brownian movement. please mark as brainliest. i worked hard for it. hope it helps you |
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| 2626. |
Answer the above question correct please |
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Answer» d ) halogen
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| 2627. |
Answrr the following attachment with suitable reasons.... Dont spammm |
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Answer» ohk. here ch3+oh will GIVE ch4.i.e. methane. plz MARK as BRAINLIEST. |
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| 2628. |
What is exothermic and endothermic reaction? give example |
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Answer» Answer: those reaction in which released heat during reaction called endothermic reaction. example:BURNING of coal. those reactions which EVOLVED heat during reaction called EXOTHERMIC reactions. example:combustion reactions. Her is answer, hope it is HELPFUL. |
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| 2629. |
Exaplain gravitation force between two objects |
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Answer» Answer: In order to calculate the gravitational force between TWO objects with masses of m1 and m2 , the equation is: where G is the gravitational constant (6.67E-11 m3 s-2 kg-1), r is the distance between the two objects, and F is the magnitude of the force between the objects. Explanation: |
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| 2630. |
Mgcl2 H2so4 CaCO3 Ca(OH) का सूत्र इकाई द्रव्यमान बताइये please answer me |
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Answer» Answer: magnesium chloride 2, sodium hydroxide 4, calcium chloride 3, calcium hydrogen is 9 |
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| 2631. |
Plz help me fast best answer brainliest |
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Answer» Explanation: |
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| 2632. |
CLASS-9Prepare oxide,chloride and sulphate of the following metals:-(a)Li(b)K(c)Ca(d)Mg(e)BaFor example:-Na=Na2O=oxide sodium oxide=Na2So4=sulphate sod.sulphate=Nacl=chloride sodium chloride |
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Answer» Answer: oxide- i) Li2O ii) K2O iii) CaO iv) MgO v) BaO chlorides- i) LICL ii) KCL iii) CACL2 iv) Mgcl2 v) Bacl2 HOPE THIS WILL HELP YOU...... PLZZ LIST MY ANSWER IN BRAINLIST..... |
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| 2633. |
Classify following into natural and synthetic fibres . cellulose ,nylon,cotton,wool |
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Answer» NATURAL fibres:
Synthetic fibres:
Hope it HELPS you. Please mark it as Brainliest and FOLLOW me!!!! |
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| 2634. |
Give some questions and answers for "is matter around us pure" |
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Answer» No . Most are IMPURE |
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| 2635. |
What are the difference between melting and boiling point of the Sulphur and oxygen |
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Answer» Explanation: Melting and boiling POINT depends on the INTERMOLECULAR FORCES of ATTRACTION between the molecules. ... Due to which Sulphur having stronger intermolecular forces has higher melting point and boiling point than OXYGEN with weaker intermolecular forces. |
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| 2636. |
I u p a c name of of complex [Ti(H20)6]3+ |
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Answer» Answer: INTERNATIONAL UNION of pure and APPLIED CHEMISTRY. |
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| 2637. |
What are the diffrent ways in which glucose is used to provide energy in various organisims |
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Answer» 1) AEROBIC respiration : In this case pyruvate is broken down into water and carbon DIOXIDE along with RELEASE of energy. It commonly occurs in mitochondria of cells. 2) Anaerobic respiration in yeast : In yeast cells during fermentation pyruvate is converted into ETHANOL and C02 in the absence of 02. |
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| 2638. |
Differentiate between compounds and molecules.(question 0f 5 marks)the best answer will be marked as brainliest |
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Answer» Answer: MOLECULE is the general term used to describe any atoms that are connected by chemical BONDS. Every combination of atoms is a molecule. A compound is a molecule made of atoms from DIFFERENT elements. All compounds are molecules, but not all molecules are compounds. Explanation: |
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| 2639. |
What do the elements in these groups have in common? a) alkali metals. b) halogens. c) noble gases. |
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Answer» they are SOFT, SHINY and EASY to cut Explanation: |
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| 2641. |
Calculate the volume of N2 required to produce 44.8 L of NO at STP. |
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Answer» Please MARK me brainliest The reaction is: N₂ + O₂ → 2NO one mole of N₂ and one mole of O₂ GAS REACT to FORM 2 moles of NO gas There are 22.4 litres of N₂ in one mole of the gas and it is also the same for O₂ gas 2 mole of NO will have 2 X 22.4 = 44.8 litres of NO is formed So, 22.4 litres of N₂ and 22.4 litres of O₂ react to form 44.8 litres of NO Hence your answer is 22.4 litres of N₂ |
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| 2642. |
Answer the attachment with reason.... Don's spam!! |
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Answer» Dude, here is your ANSWER, and please mark me brainliest The order is: b > d > c > aThis is the order because NO₂ is an electron withdrawing group and pulls electron and increases acidity. in CASE of b, ortho effect and electron withdrawing nature of NO₂ increases acidity directly on the -OH group in case of d, only electron withdrawing nature of NO₂ increases acidity in case of c, the NO₂ group increases acidity indirectly by reducing the electron DENSITY in the benzene ring in case of a, no such electron withdrawing group is PRESENT, so, a is least acidic and b is the most acidic |
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| 2643. |
What is lone pair? |
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Answer» The electron PAIRS left in the VALENCE shell without forming the bond are KNOWN as lone pairs of electrons. For EXAMPLE, ammonia molecule has ONE lone pair of electrons and water molecule has two lone pairs of electrons. |
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| 2644. |
Explian the formation of hcl molecule |
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Answer» Answer: hi the answer is in the explanation Explanation: When hydrogen chloride is dissolved in water HCl is FORMED. It is a diatomic molecule. The hydrogen and chlorine atom are connected with a single covalent bond. The bond between them is polar as the chlorine atom is more ELECTRONEGATIVE when compared with the hydrogen atom. It is strongly acidic. It is COLORLESS and viscous. It is corrosive and has a distinctively pungent SMELL. It is widely USED as a laboratory reagent and industry. It is used in the processing of leather, production of gelatin. The physical properties such as density, melting point, PH, boiling point depends on the molarity or concentration of HCl. pls mrk as brainliest plsssss can u mrk :) |
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| 2645. |
Why we should not wear polyester clothes ? what should we use instead |
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Answer» Synthetic fibers melt on heating. If they catch fire, they melt and stick to the BODY of the person WEARING it. ... We should not wear polyester clothes while WORKING in laboratory because it is prone to catch fire. There are many STRONG CHEMICALS which causes fire and polyester is also a human made fabric. |
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| 2646. |
Define saturated and unsaturated solution |
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Answer» Answer: A saturated solution is a solution that contains the MAXIMUM amount of solute that is CAPABLE of being dissolved. At 20°C, the maximum amount of NaCl that will dissolve in 100. ... An unsaturated solution is a solution that contains less than the maximum amount of solute that is capable of being dissolved. |
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| 2647. |
Question 9 - 1 MarksRespiration is a/ an |
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Answer» Answer: Biochemical process Explanation: Respiration is the biochemical process in which the CELLS of an ORGANISM OBTAIN energy by combining oxygen and GLUCOSE, resulting in the release of carbon dioxide, water, and ATP (the currency of energy in cells). |
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| 2648. |
The atomic number and mass number of an atom x is 13 and 27 respectively. How does it express along with its symbol? find the number of protons and neutrons in this atom? |
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Answer» Answer: 33protons Explanation: |
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| 2649. |
The amount of heat evolved when 500 cm^3 of 0.1 M HCl is mixed with 200 cm^3 of0.2 M NaOH is1) 1.292 kJ2) 2.292 kJ3) 3.392 kJ4) 0.292 kJ(with method please) |
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Answer» hyy mate ✌️ 500cm3 of 0.1 M HCl corresponds to 0.5×0.1=0.05 moles of hydrogen ions. 200CM3 of 0.2 M NAOH corresponds to 0.2×0.2=0.04 moles of hydroxide ions. The ENTHALPY of NEUTRALISATION is 57.3 kJ/mol. hope you are not the intended recipient |
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| 2650. |
. In the reaction of aA + bB + C Products,(i) If concentration of A is doubled, keeping conc of B and C constant, the rate of reaction be-comes double(ii) If concentration of B is halved keeping conc.of A and C constant, the rate of reactionremains unaffected(ii) If concentration of C is made 1.5 times, therate of reaction becomes 2.25 times.The order of reaction is(6) 2.5(d) 3.5Intion ? A + B Products, the order(a) 1(c)3 |
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Answer» 2.5 1 Explanation: is the answer FOLLOW me |
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