Description : Taking first period and 17 th group of the periodic table, write gradation of properties with respect to the following: a) atomic size b) Ionisation energy c) electro positivity and electro negativity.
Last Answer : The elements of 1 st period are hydrogen and helium. a) Atomic size of hydrogen is larger then that of helium because atomic size decreases across a period. b) Ionisation energy of helium ... higher as it increases down the group. Electro negativity of fluorine as it decreases down the group.
Description : (a) What are groups' and periods' in the periodic table'? (b) Two elements M and N belong to group I and II respectively and are in the same period of the periodic ... Sizes of their atoms Their metallic characters Their valencies in forming oxides Molecular formulae of their chlorides -Science
Last Answer : (a) The vertical columns in the periodic table are called groups'. The horizontal rows in the periodic table are called periods'. (b) M' and N' belong to same period but group I ... oxides. Valency goes on increasing first and then decreases. MCI, NCI2 are molecular formulae of their chlorides.
Description : La belongs to group 3 while Hg belongs to group 12 and both belong to period 6 of the periodic table.
Last Answer : La belongs to group 3 while Hg belongs to group 12 and both belong to period 6 of the ... from La to Hg together using orbital notation method.
Description : Referring to the periodic table of elements, it is found that with increasing atomic number. The atomic size in the same (A) Period increases (B) Period decreases (C) Group increases (D) Both 'b' & 'c'
Last Answer : Option D
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 : Which group of periodic table have large negative energy of activation ?
Last Answer : Which group of periodic table have large negative energy of activation ? A. Alkali metal B. Zero group C. Halogen family D. Alkaline earth metal
Description : List the elements of 15 th group of the periodic table. Name the distinct metals and non-metals of the group.
Last Answer : Nitrogen and phosphorous are non-metals. Arsenic and Antimony are metalloids, Bismuth is a metal.
Description : Atomic mass is not useful to construct the periodic table. Give reasons with an example. OR Why is atomic number is more useful than atomic mass to classify the elements?
Last Answer : Isotopes of an element have same atomic number but different atomic mass. They have to be placed in four places. This creates confusion because other elements occupied these positions.
Description : Could you use average number of neutrons instead of atomic number to build up a periodic table good as that of mendeleyev?
Last Answer : it won't be possible since some elements exixts as isotopes
Description : Are the elements on the periodic table organized by their atomic number?
Last Answer : Yes. The elements are arranged in increasing order of atomic number.
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 rows and columns are in the modern Periodic Table? A. 18 columns and 7 rows (Answer) B. 12 columns and 9 rows C. 7 columns and 18 rows D. 25 columns and 15 rows
Last Answer : A. 18 columns and 7 rows (Answer)
Description : 1The elements of the second period of the Periodic Table are given below: Li Be B C N O F (a) Give reason to explain why atomic radii decrease from Li to F. (b) Identify the most (i) metallic and (ii)non-metallic element. -Science
Last Answer : a) It is because nuclear charge increases due to increase in atomic number, therefore, force of attraction between nucleus and valence electrons increases, i.e. effective nuclear charge increases, hence ... element is ‘F’ because it can gain electrons easily due to smallest atomic size.
Description : The names of the scientists, Newlands, Mendeleev and Meyer are associated with the development of (a) Atomic structure (b) Metallurgy (c) Periodic table of elements (d) Discovery of elements
Last Answer : Ans:(c)
Description : Do we have (or will have soon) a periodic table of sub-atomic elements?
Last Answer : http://www.bing.com/images/search?q=subatomic+elements+chart&qpvt=sub+atomic+elements+chart&qpvt=sub+atomic+elements+chart&FORM=IGRE ?
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 : Proceeding across a period in the Periodic Table, what atomic size trend is observed?
Last Answer : ANSWER: ATOMIC SIZE DECREASES
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 : 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 : Which are the only two elements on the periodic table that are liquid at room temperature? A. Mercury and Bromine (Answer) B. Carbon and helium C. Nitrogen and Hydrogen D. Oxygen and Neon
Last Answer : A. Mercury and Bromine (Answer)
Description : What is the first element in the periodic table? A. Hydrogen (Answer) B. Helium C. Nitrogen D. Carbon
Last Answer : A. Hydrogen (Answer)
Description : What is the number of elements in the zero group of the periodic table ?
Last Answer : The number of elements in the zero group of the periodic table is 6 .
Description : Which one of the following statements concerning elements in the Periodic Table is correct? A Elements of the same group all have the same number of electrons in the outermost occupied electron shell. B ... (Group 17) are all gases at room temperature. E The Group 13 elements are all metals.
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 : Electro negative elements means:?
Last Answer : An atom that gains one or more electrons
Description : What is meant by electro negative?
Last Answer : Atoms which accept electrons easily are called electro negative. Ex; Chlorine.
Description : (2) Nitrogen, Phosphorous and Sodium Explanation: Fertilizer (or fertiliser) is any organic or inorganic material of natural or synthetic origin (other than liming materials) that is added to a ... essential to the growth of plants. The three elements most needed in common fertilisers are Nitrogen.
Last Answer : Metal are good conductors, because – (1) they contain free electrons (2) the molecules in them are very close to each other (3) the molecules in them collide very freely (4) they contain reflecting surface
Description : __________ is required more for leafy crops. (A) Nitrogen (B) Phosphorous (C) Potassium (D) Carbon
Last Answer : (A) Nitrogen
Description : Pick out the wrong statement. (A) Yellow phosphorous which is the most reactive allotropic form of phosphorous is transported under water (B) Apatite is the principal material present in ... fixation means the process of bringing atmospheric nitrogen into combination i.e. into nitrogen compound fo
Last Answer : (C) Urea is more hygroscopic than ammonium nitrate
Description : a) What is meant by periodicity in properties of elements with reference to the periodic table? (b) Why do all the elements of the same group have similar properties? (c) How will the tendency to gain electrons change as we go from left to right across a period? Why? -Science
Last Answer : (a) The repetition of same properties after definite interval is called periodicity in properties. (b) It is because they have same valence electrons therefore, have similar properties. (c) ... to right in a period because atomic size goes on decreasing and effective nuclear charge increases.
Description : 1st noble gas group in the periodic table?
Last Answer : Helium
Description : On going down in a group in the periodic table, the metallic nature of element
Last Answer : increases.
Description : What are rows in Periodic table called? A. Period (Answer) B. Group C. Verticals D. Perpendiculars
Last Answer : A. Period (Answer)
Description : What are Columns in Periodic table called? A. Period B. Group (Answer) C. Verticals D. Perpendiculars
Last Answer : B. Group (Answer)
Description : A sulphate salt of group 2 element of the periodic table is white ,soft substance which can be moulded into different shapes by making its dough.Identify the salt . (a) CaSO4.1/2 H2O (b) CaSO4.2H2O (c) 2CaSO4. 1⁄2 H2O (d)CaSO4
Last Answer : (a) CaSO4.1/2 H2O
Last Answer : The elements are coin metal
Description : Astatine is the element below iodine in the group `VIIA` of the periodic table. Which of the following statements is not true for astatine?
Last Answer : Astatine is the element below iodine in the group `VIIA` of the periodic table. Which of the following ... iodine molecules. D. (D) None of these.
Description : A radioactive element is preset in VIII group of the periodic table. If it emits one `alpha`particle, the new position of the nuclide will be
Last Answer : A radioactive element is preset in VIII group of the periodic table. If it emits one `alpha`particle, the new ... . VI B B. VIII C. VIIB D. I B
Description : a. 1s^2 b. 1s^22s^22p^6 In which group and period of the periodic table they are placed?
Last Answer : The electronic configuration of some elements are given below : a. 1s2 b. 1s22s22p6 In ... and period of the periodic table they are placed?
Description : In which group of elements of the modern periodic table are halogen placed ?
Last Answer : In which group of elements of the modern periodic table are halogen placed? a. 17 b. 6 c. 4 d. 2
Description : What Group is Pb (lead) in click for the periodic table?
Last Answer : Lead is in the group 14 of the Periodic Table.
Description : In the periodic table does a set of properties repeat from group to group?
Last Answer : No. The properties of elements repeat from row to row (period toperiod).The groups on the table are the columns.
Description : What is group names of periodic table?
Last Answer : Group names of Periodic Table: alkali metals, alkaline earth metals, scandium-titanium-vanadium-chromium-manganese-iron-cobalt-nickel-zinc-boron-carbon groups, pnictogens, chalcogens, halogens, noble gases.
Description : Magnesium and calcium are in the same group on the periodic table. Which sentence best explains why they have similar properties?
Last Answer : C. They both have two......
Description : What structural feature of their atoms is characteristic of elements in a group of the periodic table?
Last Answer : The Periodic Table also has a special name for its vertical columns. Each column is called a group. The elements in each group have the same number of electrons in the outer orbital. Those outer electrons are also called valence electrons.
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 : Elements present in the 2nd Group of the Periodic Table are also called ?
Last Answer : Ans alkaline earth metals
Description : Name the elements present in the 2nd Group of the Periodic Table:
Last Answer : Ans beryllium, magnesium, calcium, strontium, barium and radium