Description : As one goes across a period in the periodic table, the ionization energy generally increases for one of the following reasons. Is it because of the increasing w) atomic radius x) melting point y) nuclear charge z) density
Last Answer : ANSWER: Y -- NUCLEAR CHARGE
Description : When a radioisotope undergoes beta minus decay, does its atomic number: w) increase x) decrease y) remain the same z) vary depending on the element involved
Last Answer : ANSWER: W -- INCREASE
Description : Which one of the following is the most characteristic property of an element? (a) Density (b) Boiling point (c) Mass number (d) Atomic number
Last Answer : Ans:(d)
Description : How many of the following properties of halogen Increases with increase In atomic number. (a) Number of valence electron (b) Metallic nature (c) Boili
Last Answer : How many of the following properties of halogen Increases with increase In atomic number. (a) Number of ... . (j) `Delta_"eg"H` (magnitude wise)
Description : With increase in temperature, the atomic heat capacities of all solid elements (A) Increases (B) Decreases (C) Remains unchanged (D) Decreases linearly
Last Answer : (A) Increases
Description : With increase in the number of carbon and hydrogen atoms in hydrocarbon molecules, the density of petroleum products (A) Decreases (B) Increases (C) Remain same (D) Unpredictable from the data
Last Answer : (B) Increases
Description : Compared to Chlorine, Bromine has: w) smaller atomic size x) higher density y) lower boiling point z) greater number of outer electrons
Last Answer : ANSWER: X -- HIGHER DENSITY
Description : For an element , if atomic number (Z) and mass number (A) are 29 and 63 respectively . Then the number of protons , neutrons and electrons respectivel
Last Answer : For an element , if atomic number (Z) and mass number (A) are 29 and 63 respectively . Then the number of protons ... C. 29 , 34 ,29 D. 29 , 29 , 29
Description : An element with atomic 25 lies in group 7, then the atomic number of element which also lies in the same group is
Last Answer : An element with atomic 25 lies in group 7, then the atomic number of element which also lies in the same group is (A) 75 (B) 42 (C) 50 (D) 80
Description : An Element Atomic number 17 and mass number 36, then number of neutrons present in it–
Last Answer : 19
Description : An Element Atomic number 17 and mass number 36, then number of neutrons present in it
Description : An atom of an element with mass number 23 and atomic number 11 will have- (1) 11 neutrons, 12 protons and 11 electrons (2) 11 protons, 12 neutrons and 11 electrons (3) 11 protons, 12 electrons and 11 neutrons (4) 23 protons and 11 electrons
Last Answer : (2) 11 protons, 12 neutrons and 11 electrons
Description : All isotopes of the same element have (1) different atomic numbers and different atomic mass (2) different atomic numbers and the same atomic mass (3) the same atomic number but different atomic masses (4) the same atomic number and the atomic mass
Last Answer : (3) the same atomic number but different atomic masses Explanation: Isotopes are forms of the same element that contain equal numbers of protons but different numbers of neutrons in their nuclei. So they have the same atomic number, but differ in relative atomic mass.
Description : An element with an atomic number of 17 is - (1) an alkali metal (2) a rare gas (3) a halogen gas (4) a transition metal
Last Answer : (3) a halogen gas Explanation: Chlorine has atomic number of 17. It is a halogen gas along with fluorine (F), bromine (Br), iodine (I), and astatine (At).
Description : An atom of an element has atomic number 17 and mass number 36. The number of neutrons in its nucleus is– (1) 17 (2) 19 (3) 36 (4) 53
Last Answer : (2) 19 Explanation: Mass Number = number of protons (atomic number) + nu.sriber of neutrons. So as per the question, 36= number of neutrons + 17. Number of neutrons= 36 -17= 19
Description : The umber of neutrons present in an element having mass number 226 and atomic number 88 is– (1) 88 (2) 138 (3) 314 (4) 50
Last Answer : (2) 138 Explanation: The mass number is a count of the number of particles in an atom's nucleus which is made up of protons and neutrons. In other words, Mass Number = Number of Protons + Number of Neutrons. ... of an element, 226 = 88 + number of Neutrons. So, the number of neutrons= 226 - 88= 138.
Description : Which property of an element is always a whole number? [MP PMT 1986] (A) Atomic weight (B) Equivalent weight (C) Atomic number (D) Atomic volume
Last Answer : (C) Atomic number
Description : Which one of the following best defines the word allotropes ? A Different structural forms of an element B A pair of substances that differ by H+ C Elements that possess properties intermediate between ... a specific number of neutrons E The different phases (solid, liquid or gas) of a substance
Last Answer : A Different structural forms of an element
Description : Name this chemical element. The principal use of this element has been in solid-state electronic devices, notably transistors. Its position in the periodic table is in group "4A". The element's atomic number is 32 and its chemical symbol is Ge.
Last Answer : ANSWER: GERMANIUM
Description : I will be describing a chemical element. Try to identify it with the fewest number of clues. This chemical element is the most abundant of the rare-earth group. The element is a silver-gray metal ... factor in color television tubes. The atomic number of this element is 58. What is this element?
Last Answer : ANSWER: CERIUM (Ce)
Description : A gaseous organic compound that is best known for its use in preservative solutions has the chemical formula HCHO (read: H - C - H CHEM-92; Short Answer: Give me the name and atomic number ... element is a clear, odorless gas. This element is one of the essential ingredients in the burning process.
Last Answer : ANSWER: OXYGEN ATOMIC NUMBER = 8
Description : How many valence electrons does an atom of an element with an atomic number of twelve have?
Last Answer : ANSWER: TWO
Description : I will be describing a chemical element. Try to identify it with the fewest number of clues. This element is a halogen wh is a liquid at standard conditions. The element volatilizes readily at ro ... . The atomic number of this element is 35 and its chemical symbol is Br. Name this element.
Last Answer : ANSWER: BROMINE
Description : I will be describing a chemical element. Try to identify it with the fewest number of clues. This chemical element is a silver-white metal, with bluish tinge, capable of taking a high polish. T element ... crust and used to make drink cans. The atomic number of this element is 13. Name t element.
Last Answer : ANSWER: ALUMINUM
Description : All isotopes of the same element have ______ (1) different atomic numbers and different atomic mass (2) different atomic numbers and the same atomic mass (3) the same atomic number but different atomic masses (4) the same atomic number and the atomic mass
Last Answer : the same atomic number but different atomic masses
Description : An atom of an element has atomic number 17 and mass number 36. The number of neutrons in its nucleus is (1) 17 (2) 19 (3) 36 (4) 53
Description : The number of neutrons present in an element having mass number 226 and atomic number 88 is : (1) 88 (2) 138 (3) 314 (4) 50
Last Answer : 138
Description : The atomic mass of an element is fractional, because (A) Of uncertainty principle (B) It may have isobars (C) It contains neutrons (D) It may have isotopes
Last Answer : (D) It may have isotopes
Description : Phenol is an ortho-para director because the hydroxyl group : (a) donates electrons that increase electron density at ortho and para positions favoring nucleophilic attack. (b) donates ... para positions and attracts electrons away from meta positions favoring electrophilic attack on the ring.
Last Answer : donates electrons that increase electron density at ortho and para positions favoring electrophilic attack.
Description : If edge length of an unit cell `=4xx10^(-8)` cm and the unit cell is a face-centered cubic with atomic mass of metal is 40 then density of the unit ce
Last Answer : If edge length of an unit cell `=4xx10^(-8)` cm and the unit cell is a face-centered cubic with atomic mass of ... /(24) `gm/ml D. `(1)/(4)` gm/litre
Description : Which of the following statements is true? (a) Both salinity and density of sea increase with depth (b) Both salinity and density of sea decrease with depth (c) Salinity increase but density of sea deceases with depth (d) Salinity decreases but density of sea increases with depth
Description : The density of sea water increase as (a) depth and salinity decrease (b) depth decreases and salinity increases (c) depth increases and salinity decreases (d) depth and salinity increase
Description : If cream is removed from milk, its density – (1) Increases (2) Decreases (3) Remains the same (4) May increase or decrease
Last Answer : (1) Increases Explanation: The density of pure fresh milk being on the average 1.032, while the density of fat globules is about 0.86. It follows that the removal of cream will increase the density, while the addition of water will decrease it.
Description : The density of the liquid when heated (1) decreases (2) increases (3) does not change (4) may increase of decrease depending on pressure
Last Answer : (1) decreases Explanation: The mass density of a material varies with temperature and pressure. Increasing the temperature of a substance (with some exceptions) decreases its density by increasing the volume of ... bottom to top of the fluid due to the decrease of the density of the heated fluid.
Description : With increase in density, the viscosity of petroleum products (A) Increases (B) Decreases (C) Remain same (D) Either (A) or (B)
Description : Thermal conductivity of a gas at low density, __________ with increase in temperature. (A) Decreases (B) Increases (C) Remains unchanged (D) May increase or decrease; depends on the gas
Description : With increase in moisture content of coal, its (A) Calorific value increases sometimes (B) Bulk density always decreases (C) Clinkering tendency during combustion increases (D) None of these
Last Answer : (D) None of these
Description : With the increase in the amount of compaction energy (A) Optimum water content increases but maximum dry density decreases (B) Optimum water content decreases but maximum dry density increases ( ... and maximum dry density increase (D) Both optimum water content and maximum dry density decrease
Last Answer : Answer: Option B
Description : When the compaction energy increases the compaction of soils: (a) Both of OMC and maximum dry density decrease (b) Both of OMC and maximum dry density increase (c) OMC decreases but maximum dry density decrease (c) OMC increases but maximum dry density increase
Last Answer : (c) OMC decreases but maximum dry density decrease
Description : Generally, as altitude increases: a. Temperature decreases and density increases b. Temperature, pressure and density decreases c. Temperature and pressure increase and density decreases d. Temperature decreases and pressure and density increase
Last Answer : b. Temperature, pressure and density decreases
Description : The effects of carbon monoxide: a. Increases with altitude b. Decreases with altitude c. Increases with increase of density d. Decreases with pressure loss
Last Answer : a. Increases with altitude
Description : If cream is removed from milk, its density (1) Increases (2) Decreases (3) Remains the same (4) May increase or decrease
Last Answer : Increases
Last Answer : decreases
Description : In 1866, John Newlands, an English scientist, arranged the then known elements in the order of increasing atomic masses. He found that every eighth element had properties similar to that of the first. He called it ... of Pentamates (2) Law of musical notes (3) Law of Octaves (4) None of the above
Last Answer : (3) Law of Octaves Explanation: Newlands compared his discovery to the octaves found in music and thus, he called it the ‘Law of Octaves’. It is also known as ‘Newlands’ Law of Octaves’.
Description : In the periodic table of elements, on moving from left to right across a period, the atomic radius – (1) decreases (2) increases (3) remains unchanged (4) does not follow a definite pattern
Last Answer : (1) decreases Explanation: The atomic radius is the distance from the atomic nucleus to the outermost stable electron orbital in an atom that is at equilibrium. It tends to decrease across a period from ... usually increases while going down a group due to the addition of a new energy level (shell).
Description : In the periodic table of elements, on moving from left to right across a period, the atomic radius (1) decreases (2) increases (3) remains unchanged (4) does not follow a definite pattern
Last Answer : increases
Description : The disintegration rate of a radioactive element (A) Progressively increases (B) Progressively decreases (C) Remains constant throughout (D) May increase or decrease depending on the material
Last Answer : (B) Progressively decreases
Description : The soft silvery metalic element which ionizes easily when heated or exposed to light and is present in atomic clocks is – (1) Cerium (2) Cesium (3) Calcium (4) Californium
Last Answer : (2) Cesium Explanation: 1967, based on Einstein defining the speed of light as the most constant dimension in the universe, the International System of Units isolated two specific wave counts ... cesium has lowest ionization energy and hence it can show photoelectric effect to the maximum extent.