Description : Give reason: a) Metals are electropositive. b) Non-metals are electronegative. c) Even though hydrogen is a non-metal, it is electropositive. d) Sodium is electropositive.
Last Answer : a) Metals are electropositive. Electropositive element has the tendency to lose electrons and form cation.Metals are electron donors. Hence they are electropositive. b) Non-metals are ... is electropositive because donates electrons from last orbit to another element and becomes electropositive.
Description : Metalloids (A) Are good conductor of heat & electricity (B) Act as electron donors with metals & as electron acceptor with non metals (C) Are not necessarily solids at room temperature ... & non-metallic properties to some extent and are exemplified by elements like germanium, silicon & boron
Last Answer : D) Are compounds that exhibit both metallic & non-metallic properties to some extent and are exemplified by elements like germanium, silicon & boron
Description : Name the synthetic fibre which resembles wool in its properties. -Chemistry 9th
Last Answer : Acrylic is a strong, lightweight and warm synthetic fibre that resembles wool. It is available in a number of colours and is more durable and affordable than natural wool.
Description : Iron which resembles Cobalt and Nickel in properties has been placed far away from these elements. This was one of the limitations of : (1) Modern periodic table (2) Newland's law of octaves (3) Dobereiner's triads (4) Mendeleev's periodic table
Last Answer : (2) Newland's law of octaves Explanation: Among the major limitations of Newlands Law of Octaves, some similar elements have been separated from one another while some dissimilar elements have been placed in the same column.
Description : Give reason: Silicon is used widely even through Germanium is a better semiconductor material.
Last Answer : Silicon is the second most abundantly available material and it can be used at higher temperature. Hence it widely used than Germanium.
Description : Why do diamond and graphite have different physical properties even though they are both made of carbon?
Last Answer : Feel Free to Answer
Description : Refining process of impure metals depends upon the differences in properties of the metal. Extraction of Al is usually carried out from its bauxite or
Last Answer : Refining process of impure metals depends upon the differences in properties of the metal. ... . leaching C. liquation D. magnetic seperation
Last Answer : Refining process of impure metals depends upon the differences in properties of the metal. Extraction of Al is usually ... A D. I-D,II-A,III-C,IV-B
Description : Which of the following statements about the physical properties of metal is not correct? (a) All metals are solid except mercury (b) Most metals are hard except sodium and potassium (c) Metals are not malleable (d) Most metals are ductile
Last Answer : Ans:(c)
Description : Thorium metal (A) Resembles steel in appearance (B) Is less hard (in the range of silver) (C) Is highly ductile (D) All (A), (B) and (C
Last Answer : (D) All (A), (B) and (C
Description : Why a metal bench feels colder than a wooden one.When one sits on it on a cold morning even though both are the same temperature.Explain this observation?
Last Answer : The metal bench is a good thermal heat conductor; since yourbody is warmer than the bench the heat flows rapidly from youwarming the bench and making you feel cold.The wooden bench is apoor ... than thebench your body heat does not flow much by conductivity, so you donot feel much difference.
Description : Assertion: Many plants are propagated vegetatively even though they bear seeds. Reason: Potatoes multiply by tubers, apple by cutting etc.
Last Answer : Assertion: Many plants are propagated vegetatively even though they bear seeds. Reason: Potatoes ... both the assertion and reason are false.
Description : Mark the correct option a) Govt servant who may be convicted in a criminal court to inform his official superiors of the fact of his conviction and the circumstances b) Failure ton the part ... superior promptly even though he might have subsequently been released on bail. d) All the above
Last Answer : d) All the above
Description : Elements that show the properties of both metals and non-metals are called (a) Allotropes (b) Metalloids (c) Alloys (d) Colloids
Last Answer : Ans:(b)
Description : Elements showing properties of both met- als and non-metals are?
Last Answer : Metalloids
Description : Elements which are not distinctively metals and possess some physical properties of non- metals are called
Last Answer : metalloids.
Description : Chemical properties of Non-Metals
Last Answer : Chemical properties of Non-Metals: 1. Non-Metals form electronegative ions in a reaction. 2. Non-Metals react with water to form acidic oxides. 3. Non-Metals react with non-metals to form ionic ... reacts with acids to form salt and Hydrogen. 5. Metals are oxidizing agents as they accept electrons.
Description : Physical properties of Non-Metals
Last Answer : Physical properties of Non-Metals: 1.Non-Metals are non-lustrous except Iodine. 2.Non-Metals are not ductile nor malleable. 3.Non-Metals are bad conductor of heat & electricity. 4.Non-Metals either ... Metals are generally brittle. 6.Non-metals are not strong. 7.Non-Metals have low tensile strength.
Description : Compare chemical properties of metals and non-metals.
Last Answer : Compare chemical properties of metals and non-metals.
Description : What are the chemical properties of metals & non-metals?
Last Answer : metals electropositive, basicity, hard, ductile, malleable, sonorous nonmetals electronegative, acidic, brittle, and not all the other three properties.
Description : What are transition elements? (1) Elements whose two outermost shells are incomplete (2) Elements which possess properties of both, metals and non-metals (3) They have eight electrons in the outermost shell (4) Elements whose three outermost shells are incomplete
Last Answer : (1) Elements whose two outermost shells are incomplete
Description : Which of the following properties is generally found, in non-metals?' (1) Brittleness (2) Conductivity (3) Ductility (4) Malleability
Last Answer : (1) Brittleness Explanation: An important physical property of non metals is that they are brittle and hence cannot be beaten into sheets or drawn into wires. In other words, non-metals are non-malleable and non-ductile. Where stress is applied on nonmetals, they shatter into pieces.
Description : Which of the following are properties is generally found in non-metals
Last Answer : Brittleness
Description : Non-ferrous metals and hard steels do not exhibit a definite yield point, when pulled in the testing machine and hence for these cases, a better measure of their elastic properties is defined by the __________ stress. (A) Ultimate (B) Yield point (C) Proof (D) None of these
Last Answer : (C) Proof
Description : Give reason: Classification of elements as metals and non-metals is justified but not satisfactory.
Last Answer : Classification of elements as metals and non-metals is justified because there are more common characteristics in both the groups but it is not satisfactory because each metal or non-metal have completely different properties.
Description : Silicon is an example of - (1) A metal (2) A non- metal (3) A metalloid (4) Both (2) and (3)
Last Answer : (3) A metalloid Explanation: Metals like Na and Mg are towards the left-hand side of the Periodic Table while the non-metals like sulphur and chlorine are found on the right-hand side.
Description : What is the only non-metal element that is a liquid at room temperature and one atmosphere? w) bromine x) argon y) silicon z) selenium
Last Answer : ANSWER: W -- BROMINE
Description : Can I join the U.S. Military even though I have a non-violent felony?
Last Answer : It is possible. It won’t be easy, and you may have to get your record expunged first, but it is possible.
Description : Which of the following metals is in a liquid state at normal room temperature? (a) Sodium (b) Radium (c) Gallium (d) Silicon
Description : On a cold day when the room temperature is 15°C, the metallic cap of a pen becomes much colder than its plastic body, though both are at the same temperature of 15°C, because - (1) metals ... metals (3) metals are good conductors of heat (4) plastics have a higher thermal conductivity than metals
Last Answer : (3) metals are good conductors of heat Explanation: On a chilly day, the room temperature is lower than our body temperature. Since metals have a higher coefficient of thermal conductivity than plastic, they ... from our fingers will flow to the metal cap much more quickly than to the plastic body.
Description : On a cold day when the room temperature is 15°C, the metallic cap of a pen becomes much colder than its plastic body, though both are at the same temperature of 15°C, because : (1) metals ... metals (3) metals are good conductors of heat (4) plastics have a higher thermal conductivity than metals
Last Answer : metals are good conductors of heat
Description : During neutralization reaction acids react with ........to form ........and water. (a) Metals ,Gas (b) Bases, Salt (c) Non-Metal , Salt (d)Acids ,Salts
Last Answer : (b) Bases, Salt
Description : Explain different engineering properties of silicon carbide. Also discuss its uses.
Last Answer : Silicon carbide: Properties: Density = 3.2 g/cu.cm M.P = 2800 deg C Hardness = 9 Mohs Modulus of elasticity = 6.5 High wear resistance Excellent ... bulletproof vests Bearings Semiconductors wafer processing equipment Light emitting diode Cutting tools and burner nozzles.
Description : Why does metal make a sound when hammered and non-metals not?
Last Answer : Everything makes a sound when hit. Rigid things tend to make more sound because the vibration propagates over the whole shape quickly because the rigid thing is held tightly, so instead of just giving ... -lasting sound at one frequency. Metal is a rigid thing because of its structure. See above.
Description : Brazing is the joining of metals (A) Without melting the base metal (B) With a non-ferrous filler (C) Both (A) & (B) (D) Neither (A) nor (B)
Last Answer : Option C
Description : Rohan had learnt that non-metals on beating with hammer are generally broken into pieces. Which of the following is a non-metal? a) iron nail b)aluminium wire c)copper wire d)piece of coal
Last Answer : d)piece of coal
Description : Compare the properties of amorphous and crystalline silicon
Last Answer : morphous silicon It is a brown powder It does not conduct electricity at low temperatures. It is more reactive than crystalline silicon When heated in air, it oxidizes at the surface level ... electricity It is less reactive than amorphous silicon It does not burn in air even when heated
Description : How does silicon have similar properties as Al and P?
Last Answer : What is the answer ?
Description : Which of the following exercises most powerful influence on the mechanical properties of steel? (A) Manganese (B) Carbon (C) Phosphorous (D) Silicon
Last Answer : (B) Carbon
Description : Corrosion resisting properties of cast iron are significantly improved by the addition of 12 - 15% of (A) Tungsten (B) Vanadium (C) Silicon (D) All (A), (B) & (C)
Last Answer : (C) Silicon
Description : Which of the following alloy steels has the energy saving properties making it suitable for use in electrical machines? (A) Silicon steel (B) Chromium steel (C) Molybdenum steel (D) None of these
Last Answer : (A) Silicon steel
Description : __________ is the most important element, which controls the physical properties of steel. (A) Manganese (B) Silicon (C) Carbon (D) Vanadium
Last Answer : (C) Carbon
Description : Explain the effect of nickel, chromium, silicon, molybdenum addition on the properties of steel.
Last Answer : 1) Effect of Nickel as alloying Element: i) Provides toughness, corrosion resistance, and deep hardening. ii) Increases resistance to impact iii ) Improves tensile strength 2. Effect ... temper brittleness. iv) increases strength. V0 Mo-carbides help increase creepresistance at elevated temps
Description : Whats one thing youll never give up even though people tell you to stop?
Last Answer : Alcohol. Drunk af
Description : I am the black child of a white father, a wingless bird, flying even to the clouds of heaven. I give birth to tears of mourning in pupils that meet me, even though there is no cause for grief, and at once on my birth I am dissolved into air.Who am I? -Riddles
Last Answer : I am Smoke.
Description : I can't access my personal belongings and important documents.
Last Answer : Call the police. If you have a permanent residence there, or an apartment or a house is a common property, they must let you go.