Description : The point at which the solid, liquid and gaseous forms of a substance co-exist is called its (a) boiling point (b) melting point (c) triple point (d) freezing point
Last Answer : Ans:(c)
Description : The point at which the solid, liquid and gaseous forms of a substance co-exist is called its (a) Boiling point (b) Melting point (c) Triple point (d) Freezing point
Description : Solid and liquid phases of a substance are in equilibrium at the (A) Critical temperature (B) Melting point (C) Freezing point (D) Both (B) and (C)
Last Answer : D) Both (B) and (C)
Description : What is the amount of heat needed to turn 1 kg of the substance at its melting point from the solid to liquid state? A. Heat of fusion B. Heat of vaporation C. Heat of condensation D. Heat of fission
Last Answer : Heat of fusion
Description : What term refers to the heat needed to change a unit mass of a substance at its melting temperature from a solid into a liquid?
Last Answer : ANSWER: HEAT OF FUSION or LATENT HEAT OF FUSION or ENTHALPY OF FUSION
Description : Melting temperature of DNA is the temperature at which (A) Solid DNA becomes liquid (B) Liquid DNA evaporates (C) DNA changes from double helix into supercoiled DNA (D) Native double helical DNA is denatured
Last Answer : Answer : D
Description : Explain why o-hydroxybenzaldehyde is a liquid at room temperature while p-hydroxybenzaldehyde is a high melting solid.
Last Answer : Due to interamolecular H-bonding ortho-hydroxy benzaldehyde exists as discrete molecule whereas due to intermolecular H-bonding, p-hydroxybenzaldehyde exists as associated molecules. To break these intermolecular ... a liquid at room temperature while p-hydroxy benzaldehyde is a high melting solid.
Description : When sugar canalize on being heated above its melting point is physical change or chemical?
Last Answer : Melting is a physical process.
Description : What kind of solid tends to to have the lowest melting point?
Last Answer : Ones made of molecules
Description : If a substance is a solid at 0 degrees celcius can it have a melting point at 45 degrees celcius?
Last Answer : What is the answer ?
Description : An unknown element is a soft metallic solid. It is highly reactive and has a low melting point. In which group of the periodic table is it most likely to be found?
Last Answer : Sodium - group 1
Description : AlF3 is a high melting point solid whereas SiF4 is a gas?
Last Answer : Ans.AlF3 is an ionic solid due to large difference in electro negativity of Al and F whereas SiF4 is a covalent compound and hence only weak Vander Waals force exists between the molecules.
Description : Reaction between X and Y forms compound Z. X loses electron and Y gains electron. Which of the following properties is not shown by Z? A) Has high melting point B) Has low melting point C) Conducts electricity in molten state D) Occurs as solid
Last Answer : B) Has low melting point
Description : Which of the following properties of a solid is not dependent on crystal imperfection? (A) Ductility (B) Semi-conductivity (C) Melting point (D) Yield stress
Last Answer : (C) Melting point
Description : Which of the following is not property of sodium metal? a) lustre b)hard c)low melting point d)solid at room temperature.
Last Answer : c)low melting point
Description : The energy required to melt one mole of a solid at its melting point is called one of the following. w) the molar heat of fusion x) the molar hear of vaporization y) the molar heat of capacity z) the melting point
Last Answer : ANSWER: W -- THE MOLAR HEAT OF FUSION
Description : How could you use the physical properties of melting and boiling point to identify a substance?
Last Answer : The melting point and boiling point of a pure substance are veryspecific numbers; knowing these allows you to narrow down thepossible identity of the substance.
Description : Consider (R)- and (S)-2-butanol. Which physical property distinguishes the two compounds? (a) melting point (b) solubility in common solvents (c) Rotation of plane-polarized light (d) Infrared spectrum
Last Answer : Rotation of plane-polarized light
Description : One of the most common physical tests performed on fats is a determination of the ____ point. a. boiling c. melting b. cooling d. separating
Last Answer : c. melting
Description : For a substance, density, solubility and melting point are examples of: w) physical properties x) amorphous properties y) chemical properties z) potential properties
Last Answer : ANSWER: W -- PHYSICAL PROPERTIES
Description : Super cooling is cooling of liquid _____. (1) below melting point (2) below freezing point (3) at melting point (4) above melting point
Last Answer : (2) below freezing point Explanation: Supercooling is the process of chilling a liquid below its freezing point, without it becoming solid.
Description : Super cooling stands for cooling of a liquid – (1) at freezing point (2) below freezing point (3) at melting point (4) above melting point
Last Answer : (2) below freezing point Explanation: Supercooling, also known as undercooling, is the process of lowering the temperature of a liquid or a gas below its freezing point without it ... droplets of water below their freezing point. Refrigeration is a popular commercial application of supercooling.
Description : Ordinary glass is not a/an (A) Amorphous isotropic material (B) Supercooled liquid (C) Material with sharp definite melting point (D) Electrical insulator
Last Answer : (C) Material with sharp definite melting point
Description : __________ increases with increase in pressure. (A) The melting point of wax (B) The boiling point of a liquid (C) Both (A) and (B) (D) Neither (A) nor (B)
Last Answer : (C) Both (A) and (B)
Description : Melting point & boiling points of liquid oxygen are respectively - 218.8°C & - 183°C, while the same for liquid nitrogen is - 210°C & - 195.8°C respectively. The difference in melting points of liquid oxygen & liquid nitrogen is not equal to 8.8 (A) °C (B) °F (C) °K (D) °R
Last Answer : (B) °F
Description : Super cooling stands for cooling of a liquid : (1) at freezing point (2) below freezing point (3) at melting point (4) above melting point
Last Answer : below freezing point
Description : Is Melting coin being heated and turn black this is used as a test for metal a chemical or a physical change?
Last Answer : hg
Description : Is butter melting on warm toast physical or chemical change?
Description : Is ice cream melting a chemical change or a physical change?
Last Answer : Melting ice cream is a physical change because it has the ability to go back to it's frozen form and be ice cream again. The chemical identity of it isn't changed.
Description : What is a physical process by which vapor becomes liquid or solid the opposite of evaporation?
Last Answer : condensation
Description : What is the physical state of water at 12° C? (1) Gas (2) Solid (3) Liquid (4) Ionic
Last Answer : (3) Liquid Explanation: Water can occur in thretates solid (ice), liquid gas (vapor). It is liquid at 12 Celsius. This is the form water with which we are most familiar.
Description : Which of the following is not Powder-Based RP system? a.Selective Laser Sintering (SLS) b.Solid Object Ultraviolet-Laser Printer (SOUP) c.Electron Beam Melting (EBM) d.Direct Metal Deposition (DMD)
Last Answer : b.Solid Object Ultraviolet-Laser Printer (SOUP)
Description : Which of the following is not Solid-based RP system? a.Laminated Object Manufacturing (LOM) b.Paper Lamination Technology (PLT) c.Electron Beam Melting (EBM) d.Fused Deposition Modeling (FDM)
Last Answer : c.Electron Beam Melting (EBM)
Description : What kind of solid tends to have the solid lowest melting points?
Last Answer : Solids made up of molecules
Description : Ceramic nuclear metals compared to solid nuclear metals have (A) Higher melting points (B) Low strength at high temperature (C) More chances of radiation damage (D) Poorer corrosion resistance
Last Answer : (A) Higher melting points
Description : (a) What happens when a Ferromagnetic or Ferrimagnetic solid is heated ? (b) The ions of MgO and NaF all have the same number of electrons and intermolecular distance are about the same (235 & 215 pm). Why are the melting points are so different (2642 °C & 992 °C ?
Last Answer : (a) It changes into paramagnetic at hight temperature due to randomization of spins. (b) The ions in MgO carry two unit charges. In NaCl only one unit charge. Hence electrostatic forces of attraction in MgO are stronger.
Description : Which method, vapor phase oxidation or direct-melt process, transforms deposited material into a solid glass preform by heating the porous material without melting?
Last Answer : Vapor phase oxidation.
Description : Is melting salt a chemical reaction or physical reaction?
Last Answer : Need answer
Description : Is Snow melting is a physical or chemical?
Last Answer : It is a Physical Change. Melting it does not change whatcomponents/elements are found in snow. It is just a phase changefrom solid to liquid.
Description : Why is melting wax a physical properties of flammability is a chemical property?
Last Answer : Melting is a physical property because the chemical composition remain unchanged.Flammability is a chemical property because involve a combustion reaction.
Description : Are freezing point and melting point same with respect to change of state ? Comment.
Last Answer : Are freezing point and melting point same with respect to change of state ? Comment.
Description : When pressure is increased the melting point of ice – (1) increases (2) does not change (3) decreases (4) depends on the impurities in the ice
Last Answer : (3) decreases Explanation: In this case. if we increase the pressure on the ice the ice-water system wants to try to lower it again. It can do that by making itself fit into a ... the melting point of ice decreases because of the inversal relationship between the pressure and melting point of ice.
Description : As the molecular weight of alkanes increases, how do the boiling point and melting point change? (a) boiling point increases ; melting point increases. (b) boiling point increases ; ... decreases (d) boiling point increases ; melting point increases sequentially for alkanes over four carbons.
Last Answer : boiling point increases ; melting point increases sequentially for alkanes over four carbons.
Description : Change in volume of metals from absolute zero temperature to their melting points is (A) Almost same for all metals (B) Different for different metals (C) Less for low melting point metals (D) Less for high melting point metals
Last Answer : (A) Almost same for all metals
Description : When pressure is increased the melting point of ice (1) increases (2) does not change (3) decreases (4) depends on the impurities in the ice
Last Answer : decreases
Description : What is the point at which matter changes from a solid in a liquid?
Last Answer : This is the melting point.
Description : At triple point (for one component system), vapour pressure of solid as compared to that of liquid will be (A) More (B) Less (C) Same (D) More or less; depending on the system
Last Answer : (C) Same
Description : The point at which all the three (solid, liquid and gas) phases co-exist, is known as the __________ point. (A) Freezing (B) Triple (C) Boiling (D) Boyle
Last Answer : B) Triple
Description : At __________ point, all the three phases (i.e. solid, liquid and gas) co exist. (A) Eutectic (B) Triple (C) Plait (D) Critical
Last Answer : (B) Triple
Description : What is the unique state at which solid, liquid and gaseous phase can go co-exist in equilibrium? a. Triple point b. Critical point c. Boiling point d. Pour point
Last Answer : Triple point