When chemical reactions occur energy is always absorbed?

When chemical reactions occur energy is always absorbed?
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No, chemical reactions can be endothermic or exothermic.
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What happens when a chemical bond is formed? (1) energy is always absorbed (2) energy in always released (3) more energy is released than is absorbed (4) energy is neither released nor absorbed Correct (4) Answer – (1) energy is always absorbed Explanation: If a bond is broken, energy is released; and if a bond is formed, energy must have been absorbed. As these occur, a change in the chemical energy of the system also occurs. Within each bond of a molecule is an experimentally determined amount of enemy that upon the breaking of that bond is released into the chemical system. The energy within these bonds are 'stored' and can be easily thought of as potential energy. Upon the breaking of these bonds the energy is released thereby creating usable energy.

Description : What happens when a chemical bond is formed? (1) energy is always absorbed (2) energy in always released (3) more energy is released than is absorbed (4) energy is neither released nor ... as potential energy. Upon the breaking of these bonds the energy is released thereby creating usable energy.

Last Answer : Silver nitrate solution is kept in brown bottles in laboratory because - (1) it reacts with ordinary white bottles (2) brown bottles stops the passage of light through it (3) brown bottles do not react with it (4) brown bottles react with it

What happens when a chemical bond is formed ? (1) energy is always absorbed (2) energy in always released (3) more energy is released than is absorbed (4) energy is neither released nor absorbed

Description : What happens when a chemical bond is formed ? (1) energy is always absorbed (2) energy in always released (3) more energy is released than is absorbed (4) energy is neither released nor absorbed 

Last Answer : energy is always absorbed

Metabolism is carried out by a large class of proteins that decrease the activation energy required for chemical reactions inside a cell. Therefore they only facilitate reactions that would naturally occur at a much slower rate. What is the name of these proteins that speed up biochemical reactions?

Description : Metabolism is carried out by a large class of proteins that decrease the activation energy required for chemical reactions inside a cell. Therefore they only facilitate reactions that would naturally occur at a much slower rate. What is the name of these proteins that speed up biochemical reactions?

Last Answer : Enzymes

The minimum energy required to allow a chemical reaction to proceed is termed as the 'threshold energy '. Chemical reactions with low activation energy are: (A) Always irreversible (B) Insensitive to temperature changes (C) Mostly irreversible (D) Highly temperature sensitive

Description : The minimum energy required to allow a chemical reaction to proceed is termed as the 'threshold energy '. Chemical reactions with low activation energy are: (A) Always irreversible (B) Insensitive to temperature changes (C) Mostly irreversible (D) Highly temperature sensitive

Last Answer : (B) Insensitive to temperature changes

Do Chemical reactions occur at the same rate no matter what the size of the reactant particles?

Description : Do Chemical reactions occur at the same rate no matter what the size of the reactant particles?

Last Answer : Need answer

. Photo-chemical reactions occur in presence of (A) Sunlight (B) Darkness (C) Solid catalysts (D) Monochromatic radiation only

Description : . Photo-chemical reactions occur in presence of (A) Sunlight (B) Darkness (C) Solid catalysts (D) Monochromatic radiation only

Last Answer : (A) Sunlight

An ___________ solution which consists of solutes in water, is essential for chemical reactions to occur. a. hydrophobic b. aqueous c. covalent d. vitreous

Description : An ___________ solution which consists of solutes in water, is essential for chemical reactions to occur. a. hydrophobic b. aqueous c. covalent d. vitreous

Last Answer : b. aqueous

Chemical reaction in which light energy is either absorbed or released?

Description : Chemical reaction in which light energy is either absorbed or released?

Last Answer : Photochemical reaction

What is the energy absorbed during chemical reaction under constant volume conditions?  A. Entropy  B. Ion exchange  C. Enthalpy  D. Enthalpy of reaction

Description : What is the energy absorbed during chemical reaction under constant volume conditions?  A. Entropy  B. Ion exchange  C. Enthalpy  D. Enthalpy of reaction

Last Answer : Enthalpy

An isolated system is one in which  (a) mass does not cross boundaries of the system, though energy may do so  (b) neither mass nor energy crosses the boundaries of the system  (c) both energy and mass cross the boundaries of the system  (d) mass crosses the boundary but not the energy  (e) thermodynamic reactions do not occur.

Description : An isolated system is one in which  (a) mass does not cross boundaries of the system, though energy may do so  (b) neither mass nor energy crosses the boundaries of the system  (c) both ... system  (d) mass crosses the boundary but not the energy  (e) thermodynamic reactions do not occur.

Last Answer : Answer : b

An open system is one in which  (a) mass does not cross boundaries of the system, though energy may do so  (b) neither mass nor energy crosses the boundaries of the system  (c) both energy and mass cross the boundaries of the system  (d) mass crosses the boundary but not the energy  (e) thermodynamic reactions do not occur.

Description : An open system is one in which  (a) mass does not cross boundaries of the system, though energy may do so  (b) neither mass nor energy crosses the boundaries of the system  (c) both energy ... system  (d) mass crosses the boundary but not the energy  (e) thermodynamic reactions do not occur.

Last Answer : Answer : c

The preferred route of administration of medication in the most acute care situations is which of the following routes? a) Intravenous The IV route is the preferred parenteral route in most acute care situations because it is much more comfortable for the patient, and peak serum levels and pain relief occur more rapidly and reliably. b) Epidural Epidural administration is used to control postoperative and chronic pain. c) Subcutaneous Subcutaneous administration results in slow absorption of medication. d) Intramuscular Intramuscular administration of medication is absorbed more slowly than intravenously administered medication.

Description : The preferred route of administration of medication in the most acute care situations is which of the following routes? a) Intravenous The IV route is the preferred ... ) Intramuscular Intramuscular administration of medication is absorbed more slowly than intravenously administered medication.

Last Answer : a) Intravenous The IV route is the preferred parenteral route in most acute care situations because it is much more comfortable for the patient, and peak serum levels and pain relief occur more rapidly and reliably.

Bioavailability differences among oral formulations of a drug are most likely to occur if the drug: A. Is freely water soluble B. Is completely absorbed C. Is incompletely absorbed D. Undergoes little first-pass metabolism

Description : Bioavailability differences among oral formulations of a drug are most likely to occur if the drug: A. Is freely water soluble B. Is completely absorbed C. Is incompletely absorbed D. Undergoes little first-pass metabolism

Last Answer : C. Is incompletely absorbed

Bioavailability differences among oral formulations of a drug are most likely to occur if the drug: A. Is freely water soluble B. Is completely absorbed C. Is incompletely absorbed D. Undergoes little first-pass metabolism

Description : Bioavailability differences among oral formulations of a drug are most likely to occur if the drug: A. Is freely water soluble B. Is completely absorbed C. Is incompletely absorbed D. Undergoes little first-pass metabolism

Last Answer : C. Is incompletely absorbed

When white light passes through a red plate of glass and then through a green plate of glass which one of the following things occur? w) the light is totally absorbed x) the light that emerges is a combination of red and green y) the light that emerges lacks only its red and green components z) the light that emerges is green

Description : When white light passes through a red plate of glass and then through a green plate of glass which one of the following things occur? w) the light is totally absorbed x) the light that emerges is ... ) the light that emerges lacks only its red and green components z) the light that emerges is green

Last Answer : ANSWER: W -- THE LIGHT IS TOTALLY ABSORBED

Reactions with high activation energy are (A) Very temperature sensitive (B) Temperature insensitive (C) Always irreversible (D) Always reversible

Description : Reactions with high activation energy are (A) Very temperature sensitive (B) Temperature insensitive (C) Always irreversible (D) Always reversible

Last Answer : (A) Very temperature sensitive

The reactions with low activation energy are (A) Always spontaneous (B) Slow (C) Fast (D) Non-spontaneous

Description : The reactions with low activation energy are (A) Always spontaneous (B) Slow (C) Fast (D) Non-spontaneous

Last Answer : (C) Fast

Pick out the wrong statement. (A) Visible radiation provides the necessary activation energy in photochemical reactions (B) The order and molecularity of a complex reaction may not be the same (C) For a second order reaction, the slope of the graph/plot between rate and (concentration) is equal to the rate constant (k) (D) Molecularity of the reaction is always a whole number greater than zero

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Last Answer : (B) The order and molecularity of a complex reaction may not be the same

Pick out the wrong statement. (A) Surface tension of a substance vanishes at critical point, as there is no distinction between liquid and vapour phases at its critical point (B) Entropy of a system decreases with the evolution of heat (C) Change of internal energy is negative for exothermic reactions (D) The eccentric factor for all materials is always more than one

Description : Pick out the wrong statement. (A) Surface tension of a substance vanishes at critical point, as there is no distinction between liquid and vapour phases at its critical point (B) Entropy of ... is negative for exothermic reactions (D) The eccentric factor for all materials is always more than one

Last Answer : (D) The eccentric factor for all materials is always more than one

Solar energy is due to – (1) fusion reactions (2) fission reactions (3) combustion reactions (4) chemical reactions

Description : Solar energy is due to – (1) fusion reactions (2) fission reactions (3) combustion reactions (4) chemical reactions

Last Answer : (1) fusion reactions Explanation: Nuclear Fusion Reaction is the process which is responsible for the sun to radiate energy in the form of light and heat commonly known as solar energy. Fusion ... and pressure to create a denser helium atom releasing, in the process, colossal amounts of energy.

Pick out the wrong statement. (A) In a multistep reaction, the slowest step is the rate determining step (B) In general, the rate of a reaction becomes triple for every 10°C rise in temperature (C) Slow chemical reactions have generally high values of activation energy (D) Molecularity of a reaction cannot be zero but the order of a reaction can be zero

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Last Answer : (B) In general, the rate of a reaction becomes triple for every 10°C rise in temperature

Pick out the correct statement. (A) Reactions with high activation energies are very temperature sensitive (B) Chemical equilibrium is a static state (C) A photochemical reaction is catalysed by light (D) A chemical reaction occurs when the energy of the reacting molecule is less than the activation energy of the reaction

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Last Answer : (A) Reactions with high activation energies are very temperature sensitive (B) Chemical equilibrium is a static state

Pick out the wrong statement: (A) Chemical reactions with high activation energy are very temperature sensitive (B) A flat velocity profile exists in a plug flow reactor (C) The residence time for all the elements of fluid in case of a P.F.R. need not be same (D) Half life of a reaction increases with increased initial concentration for reaction orders more than one

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Last Answer : (C) The residence time for all the elements of fluid in case of a P.F.R. need not be same

Pick out the wrong statement. (A) Catalytic activity of enzyme catalysed reactions which is affected by temperature, pH value & chemical agents, is maximum at a temperature of about 45°C(B) Most of the enzyme catalysed reactions involve at least two substrates (C) Enzymes help in increasing the activation energy of the reaction (D) Equilibrium concentrations in enzyme catalysed reactions can be calculated by using the thermodynamic properties of substrates & prod

Description : Pick out the wrong statement. (A) Catalytic activity of enzyme catalysed reactions which is affected by temperature, pH value & chemical agents, is maximum at a temperature of about 45°C ... in enzyme catalysed reactions can be calculated by using the thermodynamic properties of substrates & prod

Last Answer : (C) Enzymes help in increasing the activation energy of the reaction

Pick out the correct statement. (A) In catalytic reactions, the catalyst reacts with the reactants (B) A catalyst initiates a chemical reaction (C) A catalyst lowers the activation energy of the reacting molecules (D) A catalyst cannot be recovered chemically unchanged at the end of the chemical reaction

Description : Pick out the correct statement. (A) In catalytic reactions, the catalyst reacts with the reactants (B) A catalyst initiates a chemical reaction (C) A catalyst lowers the activation energy of ... molecules (D) A catalyst cannot be recovered chemically unchanged at the end of the chemical reaction

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Which one of the following statements regarding a catalyst is not correct? A An enzyme is a catalyst that only binds certain substrates. B An enzyme is a protein that is a highly efficient catalyst for one or more chemical reactions in a living system. C Catalysts increase the rate of a reaction by altering the mechanism, thereby increasing the activation energy. D Catalysts do not alter the equilibrium constant for a chemical reaction.

Description : Which one of the following statements regarding a catalyst is not correct? A An enzyme is a catalyst that only binds certain substrates. B An enzyme is a protein that is a highly ... increasing the activation energy. D Catalysts do not alter the equilibrium constant for a chemical reaction.

Last Answer : C Catalysts increase the rate of a reaction by altering the mechanism, thereby increasing the activation energy.

Solar energy is due to (1) fusion reactions (2) fission reactions (3) combustion reactions (4) chemical reactions

Description : Solar energy is due to (1) fusion reactions (2) fission reactions (3) combustion reactions (4) chemical reactions 

Last Answer : fusion reactions

$ Soil soluiton is absorbed by all the parts of a root . ! Soil solution is always of a high concentration.

Description : $ Soil soluiton is absorbed by all the parts of a root . ! Soil solution is always of a high concentration.

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What can be absorbed or released as the result if a chemical reaction?

Description : What can be absorbed or released as the result if a chemical reaction?

Last Answer : Heat

What can be absorbed or released as the result of a chemical reaction?

Description : What can be absorbed or released as the result of a chemical reaction?

Last Answer : Energy.

Chemical reaction in which electric en- ergy is either absorbed or released?

Description : Chemical reaction in which electric en- ergy is either absorbed or released?

Last Answer : Electro chemical reaction

n a chemical factory where dyes are made, wet cake at 30 OC consisting of 60% moisture is put in a dryer to obtain an output having only 5% moisture, at atmospheric pressure. In each batch about 120 kgs of material is dried. a. The quantity of moisture removed per batch. b. What is the total quantity ( sensible & latent) of heat required to evaporate the moisture, if the latent heat of water is 540 kcal/kg at atmospheric conditions, Ignore heat absorbed by the solids c. Find the quantity of steam required for the drying process (per batch), if steam at 4 kg/cm2 is used for generating hot air in the dryer and the dryer efficiency is 80%. Latent heat of steam at 4 kg/cm2 is 520 kcal/kg.

Description : n a chemical factory where dyes are made, wet cake at 30 OC consisting of 60% moisture  is put in a dryer to obtain an output having only 5% moisture, at atmospheric pressure. In  each batch about 120 ... dryer and the dryer efficiency  is 80%. Latent heat of steam at 4 kg/cm2 is 520 kcal/kg.

Last Answer : Given that   Qty of material dried per batch - 120 Kgs  Moisture at inlet - 60% a. The quantity of moisture removed per batch.  Water quantity in a wet batch - 120 x 0.6 = 72 Kgs.  Quantity of bone dry ... - 48/0.95 = 50.5 Kgs.  Equivalent water in a dry batch - 50.5 - 48 = 2.5 Kgs.

In which cell organelle do photo and thermochemical reactions occur in different sites ? -Do You Know?

Description : In which cell organelle do photo and thermochemical reactions occur in different sites ? -Do You Know?

Last Answer : answer:

Which of the following reactions does not occur in Bessemer converter in the extraction of copper from chalcopyrites ?

Description : Which of the following reactions does not occur in Bessemer converter in the extraction of copper from chalcopyrites ?

Last Answer : Which of the following reactions does not occur in Bessemer converter in the extraction of copper from chalcopyrites ... 2Cu_(2)O rarr 6Cu + SO_(2)`

Which one of the following reactions occur during smelting in the reduction zone at lower temperature(in iron metallurgy)?

Description : Which one of the following reactions occur during smelting in the reduction zone at lower temperature(in iron metallurgy)?

Last Answer : Which one of the following reactions occur during smelting in the reduction zone at lower temperature(in iron ... CO` D. `CO_(2)+C rarr 2CO`

Which one of the following reactions does not occur ?

Description : Which one of the following reactions does not occur ?

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Where in the chloroplast does light reactions of photosynthesis occur?

Description : Where in the chloroplast does light reactions of photosynthesis occur?

Last Answer : Light- independent reactions of photosynthesis occur in thestroma of the chloroplasts of a cell.

Do displacement reactions only occur between halogens?

Description : Do displacement reactions only occur between halogens?

Last Answer : Also other elements can be involved.

What reactions occur in a cytoplasm?

Description : What reactions occur in a cytoplasm?

Last Answer : What is the answer ?

Template/lock and key theory of enzyme action is supported by (A) Enzymes speed up reaction (B) Enzymes occur in living beings and speed up certain reactions (C) Enzymes determine the direction of reaction (D) Compounds similar to substrate inhibit enzyme activity

Description : Template/lock and key theory of enzyme action is supported by (A) Enzymes speed up reaction (B) Enzymes occur in living beings and speed up certain reactions (C) Enzymes determine the direction of reaction (D) Compounds similar to substrate inhibit enzyme activity

Last Answer : Answer : D

Enzyme catalysed reactions occur in (A) Pico seconds (B) Micro seconds (C) Milli seconds (D) None of these

Description : Enzyme catalysed reactions occur in (A) Pico seconds (B) Micro seconds (C) Milli seconds (D) None of these

Last Answer : Answer : C

Where do most allergic reactions occur ?

Description : Where do most allergic reactions occur ?

Last Answer : Most of them occur on mucous membrane. Allergens enter the body by the process of inhalation or ingestion.

The reaction in which the forward and backward reactions occur simultaneously is called?

Description : The reaction in which the forward and backward reactions occur simultaneously is called?

Last Answer : Reversible reaction

The reaction in which the forward and backward reactions occur simultaneously is called?

Description : The reaction in which the forward and backward reactions occur simultaneously is called?

Last Answer : Reversible reaction

Dark reactions of photosynthesis occur in (a) granal thylakoid membranes (b) stromal lamella membranes (c) stroma outside photosynthetic lamellae (d) periplastidial space.

Description : Dark reactions of photosynthesis occur in (a) granal thylakoid membranes (b) stromal lamella membranes (c) stroma outside photosynthetic lamellae (d) periplastidial space.

Last Answer : c) stroma outside photosynthetic lamellae

Which one of the following aspects is an exclusive characteristic of living things? (a) Isolated metabolic reactions occur in vitro (b) Increase in mass from inside only (c) Perception of events happening in the environment and their memory. (d) Increase in mass by accumulation of material both on surface as well as internally

Description : Which one of the following aspects is an exclusive characteristic of living things? (a) Isolated metabolic reactions occur in vitro (b) Increase in mass from inside only (c) Perception of events ... memory. (d) Increase in mass by accumulation of material both on surface as well as internally

Last Answer : (d) Increase in mass by accumulation of material both on surface as well as internally.

Ionic reactions occur in (A) Solid state only (B) Liquid state only (C) Solutions (D) Any state

Description : Ionic reactions occur in (A) Solid state only (B) Liquid state only (C) Solutions (D) Any state

Last Answer : (C) Solutions

What is needed in order for reactions to occur at body temperatures? a. buffers b. acids c. bases d. enzymes

Description : What is needed in order for reactions to occur at body temperatures? a. buffers b. acids c. bases d. enzymes

Last Answer : d. enzymes

In which cell organelle do photo and thermochemical reactions occur in different sites?

Description : In which cell organelle do photo and thermochemical reactions occur in different sites?

Last Answer : Chloroplasts

In protolytic reactions in which the reactants are much stronger as an acid and a base than the products, the proton transfer reaction: w) does not occur x) approaches completeness y) produces a much stronger acid and a much weaker base z) produces a much weaker acid and a much stronger base

Description : In protolytic reactions in which the reactants are much stronger as an acid and a base than the products, the proton transfer reaction: w) does not occur x) approaches completeness y) produces a much stronger acid and a much weaker base z) produces a much weaker acid and a much stronger base

Last Answer : ANSWER: X -- APPROACHES COMPLETENESS