Description : What is the melting point of phosphorus ?
Last Answer : The melting point of phosphorus is 44 degrees Celsius.
Description : The material used for a fuse wire should have (a) high resistivity (b) high ductility (c) high melting point (d) low melting point
Last Answer : Ans:(d)
Description : Metals have ______. (1) High melting and boiling point (2) Low melting and boiling point (3) High melting and low boiling point (4) Low melting and high boiling point
Last Answer : (1) High melting and boiling point
Description : In arc welding, Argon is used because of its - (1) Low reactivity with metal (2) Ability to lower the melting point of the metal (3) High flammability (4) High calorific value
Last Answer : (1) Low reactivity with metal Explanation: In arc welding, Argon is used as a shielding gas because it is chemically inert and forms no compounds. At the high temperatures that welding requires, the ... to brittle welds and instability in the welding arc. So,argon and other inert gases are sprayed.
Description : A Fuse wire is characterized by – (1) High resistance and low melting point (2) High resistance and high melting point (3) Low resistance and high melting point (4) Low resistance and low melting point
Last Answer : (4) Low resistance and low melting point Explanation: A fuse is a type of low resistance resistor that acts as a sacrificial device to provide over current protection, of either the load or source ... melt if a current more than the safe current for the appliance starts flowing through the circuit.
Description : The nature of .fuse wire is – (1) high resistance and low melting point. (2) high resistance and high melting point. (3) low resistance and high melting point. (4) low resistance and low melting point.
Last Answer : (1) high resistance and low melting point. Explanation: A fuse or fusable link works by opening an electrical circuit when the current becomes too high. As the current increases, the temperature ... be connected in series with the appliance. Besides, it should have a comparatively high resistance.
Description : For photoelectric effect to take place, the metal used as the cathode should have – (1) high melting point (2) low melting point (3) low work function (4) low resistance
Last Answer : (3) low work function Explanation: The photoelectric effect is the propensity of high-energy electromagnetic radiation to eject electrons from a given material. The photoelectric effect has been utilized in devices called photocells, consisting of two electrodes in a sealed vacuum tube.
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 : Sudden temperature fluctuation does not affect pyrex glass, because of its (A) Low co-efficient of expansion (B) High co-efficient of expansion (C) High melting point (D) Both (B) and (C)
Last Answer : (A) Low co-efficient of expansion
Description : Pick out the wrong statement. (A) Low intensity explosives are also called propellants, whereas high intensity explosive are called detonators (B) Gun powder comprises of 75% salt petre, 15% charcoal ... TNT is a hygroscopic explosive having very high melting point and is non-toxic to human being
Last Answer : (D) TNT is a hygroscopic explosive having very high melting point and is non-toxic to human being
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 : The melting point of fuse wire should be high or low?
Last Answer : low
Description : The material used for fuse must have (a) low melting point and high specific resistance (b) low melting point and -low specific resistance (c) high melting point and low specific resistance (d) low melting point and any specific resistance
Last Answer : (a) low melting point and high specific resistance
Description : Refractory metals are known for which of the following properties: w) lack of chemical reactivity x) low density y) high melting point z) high thermal conductivity
Last Answer : ANSWER: Y -- HIGH MELTING POINT
Description : In arc welding, Argon is used because of its (1) Low reactivity with metal (2) Ability to lower the melting point of the metal (3) High flammability (4) High calorific value
Last Answer : Low reactivity with metal
Description : For photoelectric effect to take place, the metal used as the cathode should have______ (1) high melting point (2) low melting point (3) low work function (4) low resistance
Last Answer : low work function
Description : A Fuse wire is characterised by (1) High resistance and low melting point (2) High resistance and high melting point (3) Low resistance and high melting point (4) Low resistance and low melting point
Last Answer : Low resistance and low melting point
Description : The nature of fuse wire is (1) high resistance and low melting point. (2) high resistance and high melting point. (3) low resistance and high melting point. (4) low resistance and low melting point.
Last Answer : high resistance and low melting point.
Description : Phosphorus is kept in water because – (1) its ignition temperature is very high (2) its ignition temperature is very low (3) its critical temperature is high (4) its critical temperature is low
Last Answer : (2) its ignition temperature is very low Explanation: The allotropic form of Phosphorus (white phosphorus) is less stable and therefore highly reactive because of angular strain in P4 molecule where the angles are only 600.
Description : Phosphorus is kept in water because (1) its ignition temperature is very high (2) its ignition temperature is very low (3) its critical temperature is high (4) its critical temperature is low
Last Answer : its ignition temperature is very low
Description : What terms describe a substance that has a low melting point and poor electrical conductivity?
Last Answer : covalent and molecular
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 : The filament of an electric lamp becomes white hot but the lead-in wires holding the filament are only slightly heated because they (a) have smaller current passing through them (b) have very low resistance (c) have higher melting point (d) are made of black iron
Last Answer : Ans:(b)
Description : Safety fuse wire used in domestic electrical appliances is made of metal of low (1) Resistance (2) Melting point (3) Specific gravity (4) Conductance
Last Answer : (2) Melting point Explanation: The fuse wire is based on the Joules law of heating which says that when the electric current is allowed to pass through a conductor, the conductor heats up and is ... . For this purpose the material used as fuse wire should have high resistance and low melting point.
Description : Alloy having low melting point?
Last Answer : Solder
Description : Polymerisation of poly functional monomers produces polymers having (A) Good mechanical strength (B) Low viscosity (C) Low melting point (D) None of these
Last Answer : (A) Good mechanical strength
Description : Method of separating metals which have low melting point I from an ore is?
Last Answer : Liquation
Description : Which of the following is a low melting point metal? (A) Stainless steel (B) Wrought iron (C) Tin (D) Copper
Last Answer : (C) Tin
Description : Hydrometer measures the specific gravity of liquids based on the principles of buoyancy. Pycnometer is used to measure the specific gravity of (A) Powder & granular solids (B) Liquids (C) Low melting point semi-solids (D) All 'a', 'b' & 'c
Last Answer : (D) All 'a', 'b' & 'c
Description : Prilling of urea should be accomplished (in a sprayer) just above the melting point of urea with minimum of retention time, otherwise it will result in (A) Low bulk density product (B) Biuret formation (C) Non-spherical prills (D) Substantially wet non-flowing and sticky product
Last Answer : (B) Biuret formation
Description : Hot dipping process is used for coating a low melting point metal (e.g. Pb, Sn, Zn) on iron, steel & copper having relatively higher melting points. Which of the following is not a hot dipping process? (A) Galvanising (B) Tinning (C) Sherardizing (D) None of these
Last Answer : (C) Sherardizing
Description : Pick up the correct statement from the following: (A) Plastics have generally low melting point (B) The coefficient of thermal expansion of plastics is about three times than that of steel (C) ... fibre-glass with phenolic resins has absorption coefficient of about 0.67 (D) All the above
Last Answer : Answer: Option D
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 : Give reason .the melting point and boiling point of alkali metals are low
Last Answer : The melting and boiling points of the alkali metals are low indicating weak metallic bonding due to the presence of only a single valence electron in them.
Last Answer : Melting point
Description : Can ionic substances have high or low melting points?
Last Answer : Generally ionic substances have high melting and boiling points.
Description : The melting and boiling points of ionic solids are (a) High (b) Low (c) Very low (d) Of intermediate range
Last Answer : Ans:(a)
Description : Why is it a poor practice to use a high wattage soldering iron when soldering or desoldering components on a printed circuit board? A. The circuit board will blister and warp. B. The foil wire bonded ... board has a low melting temperature. D. The solder is kept to a dull heat dissipating finish.
Last Answer : Answer: B
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 : Pick out the wrong statement pertaining to the properties of glasses. Glasses generally have (A) High electrical insulation properties (B) Sharp melting points (C) Low co-efficient of thermal expansion (D) Compressive strength much greater than their tensile strengths
Last Answer : (B) Sharp melting points
Description : Which of the following is false? a) electricity is high-grade energy b) high grade forms of energy are highly ordered and compact c) low grade energy is better used for applications like melting of metals rather than heating water for bath
Last Answer : c) low grade energy is better used for applications like melting of metals rather than heating water for bath
Description : My soil is poor, very low in Nitrogen, phosphorus and potash. How do I correct it?
Last Answer : Need Answer
Description : Addition of lead, sulphur and phosphorus to low carbon steel helps in improving its (A) Corrosion resistance (B) Tensile strength (C) Machinability (D) Compressive strength
Last Answer : (C) Machinability
Description : Metals are good conductors of electricity because (a) The contain free electrons (b) The atoms are lightly packed (c) They have high melting point (d) All of the above
Description : Nichrome wire is used in an electric heater because _______. (1) It has high resistance (2) It has high melting point (3) It can resist a current upto approx 5 amperes (4) For all of the above reasons
Last Answer : (4) For all of the above reasons
Description : Metals are good conductors of electricity because - (1) they contain free electrons (2) the atoms are lightly packed (3) they have high melting point (4) All of the above
Last Answer : (1) they contain free electrons Explanation: Copper is used for electrical wiring because it is a good conductor of electricity. Metal particles are held together by strong metallic bonds, which is why they have high melting and boiling points.
Description : Tungsten is used for the manufacture of the filament of an electric bulb, because – (1) It is a good conductor (2) It is economical (3) It is malleable (4) It has a very high melting point
Last Answer : (4) It has a very high melting point Explanation: Tungsten is used because it has the highest melting point of all the metallic elements. It melts at 3410 degrees Celsius. When current passes ... bulb. The first successful light bulb filaments were made of carbon (from carbonized paper or bamboo).
Description : Metals are good conductors of electricity because – (1) they contain free electrons (2) the atoms are lightly packed (3) they have high melting point (4) All of the above
Description : Presence of high phosphorous in cast iron increases its (A) Fluidity (B) Melting point (C) Shrinkage (D) Tensile strength
Last Answer : (A) Fluidity
Description : Which of the following will have the highest melting point? (A) Pig iron (B) Mild steel (C) Wrought iron (D) High carbon stee
Last Answer : (C) Wrought iron