and ns orbitals and (b) extra stability of half filled and completely filled orbitals in case of Cr and Cu in 3d series. Cr : Is 2 2s2 2p6‚ 3s2 3p6 4s1 3d5 Cu : Is2 2s2 2p6‚ 3s2 3p6 4s1 3d10 To write the electronic configuration of Mn+‚ the electrons are first removed from ns orbital and then from (n - 1) d orbitals of neutral‚ atom (if required). For example‚ the electronic configuration of Cu+‚ Cu2+ and Cr3+ are respectively 3d10 4s°‚ 3d9 4s° and 3d3 4s°. m o .c y a d with the help of above. The
Premium Periodic table Transition metal Electron configuration
I bought a new security token and all I got was this lousy phish— Relay attacks on visual code authentication schemes Graeme Jenkinson‚ Max Spencer‚ Chris Warrington‚ Frank Stajano {graeme.jenkinson‚ max.spencer‚ chris.warrington‚ frank.stajano}@cl.cam.ac.uk University of Cambridge Computer Laboratory‚ Cambridge‚ UK Abstract. One recent thread of academic and commercial research into web authentication has focused on schemes where users scan a visual code with their smartphone‚ which is a convenient
Premium Authentication
r Lab Report 5 Introduction to the Classes of Chemical Reactions Course: Chem. 1151L‚ Tuesday & Thursday June 23‚ 2011 Mr. Nasir Uddin Pre Lab Questions: 1. CaBr2 (aq) + K3PO4 (aq) → CA(PO4)2(S) + KBr (aq) = Ca3(PO4)2 + 6 KBr Double Replacement 2. Li(s) + O2(g) = Li2O(s) =2 Li2O Decomposition 3. CH4 + O2 = CO2 + H2O = CO2 + 2 H2O Combination 4. AgBr(s) = Ag (s) + Br2(l) = 2 Ag + Br2 Combination 5. Mg(s) + H2SO4 (aq) = MgSO4 + H2
Premium Chemical reaction Chemistry Hydrogen
Aim To prepare a sample of cuprammonium rayon threads from filter paper Apparatus Required a) Conical flask (preferably 250 ml) b) Funnel c) Glass rod d) Beaker (preferably 250 ml) e) Water bath f) Filter paper (Whatman paper or ordinary filter paper sheets. Preferably‚ Whatman) Chemicals Required a) CuSO4 b) NaOH solution c) Liquor ammonia solution d) Dilute H2SO4 e) Whatman Paper f) Distilled H2O Background Rayon is a synthetic
Premium Cellulose Sodium hydroxide Paper
X-ray Absorption Spectroscopy X-ray absorption spectroscopy (XAS) techniques probe short- and medium-range order‚ yielding information on bond lengths‚ coordination numbers‚ local coordination geometry and the oxidation state of atoms for a wide range of solid and liquid systems. XAS experiments require an intense‚ tunable photon source only available at synchrotrons. Features • medium and high energy (from atomic number Z=20 upwards) XAS‚ XANES (x-ray absorption near-edge structure)
Premium Chemistry Spectroscopy Metal
to call his parliament back. The parliament then sent the king a list of demands that he had to agree to if they were to provide him with more money. In August 1642‚ Charles declared war against parliament. The Civil War went on for four years until 1646 when Charles was captured. Finally‚ in 1648‚ Charles tried to start another war with parliament from captivity. This was an important reason why their relationship got worse because before Civil War‚ Parliament would have raised their own‚ more superior
Free Charles I of England Charles II of England
Honors Chemistry Final Exam Study Guide Multiple Choice- (51 points @ 1/2 point ea.) Identify the letter of the choice that best completes the statement or answers the question. ____ 1. The pair of elements that forms a bond with the least ionic character is |a. |Na and Cl. |c. |O and Cl. | |b. |K and Cl. |d. |Mg and Cl.
Premium Atom Chemical bond Electron
are in a post 1982 penny? - (2.496 x 0.975) = 2.43 g of Zinc (2.496 x 0.025) = 0.062 g of Copper 4. How many moles of copper and zinc are in post 1982 pennies? (2.43 g Zn x 1 mol Zn) / 63.38 g Zn = 0.037 mol Zn (0.062 g Cu x 1 mol Cu) / 63.54 g Cu = 0.00097 mol Cu 5. Write a balanced reaction of zinc with HCl. - Zn (s) + 2HCl (aq) ZnCl2 (aq) + H2 (g) 6. How many moles of HCl are needed to react completely with all of the zinc in a post 1982 penny? (2.43 g Zn x 1 mol) / 65.38 g Zn = 0
Premium Chemistry Chemical reaction Concentration
JEET SCIENCE ACADEMY CHOWK AZAM (LAYYAH) TIME 2.5 Hr CHEMISTRY 1st YEAR CH # 1‚2‚9‚10 Marks: 85 G.Super . 1 Name…………………………………………...... Objective ROLL NO. ………………………………. Q.NO.1. Encircle the correct answer? (1×17=17) 1. Atoms of which one of the follelement have independent existance: (A) Flourine (B) Krypton (C ) Oxygen (D) Nitrogen 2.18g glucose is dissolved
Premium Electrochemistry Hydrogen Vitamin C
Pd.3 09/11/11 Culture Clash in the Chesapeake By the time the English arrived‚ Powhatan was the head of the Indians‚ dominating a few dozen tribes in the James River area. Initially‚ the Indians considered the English as potential allies because the English helped them to control other Indian tribes in the region. However‚ the relationship between them aggravated as time went on. One of the reasons is because the different languages and cultures caused general precautions. But‚ more importantly
Premium Native Americans in the United States English people Pocahontas