A. metallic B. covalent (polar) C. ionic D. covalent (non-polar) 9. The number of moles of ions in 1 mol of copper(II)phosphate is A. 1 B. 2 C. 4 D. 5
The average bond enthalpies for O—O and O==O are 146 and 496 kJ mol−1 respectively. What is the enthalpy change, in kJ, for the reaction below? H—O—O—H(g) ® H—O—H(g) + ½O==O(g) A. – 102 B. + 102 C. + 350 D. + 394 (1) 7.
Find the volume of 2.40 mol of gas whose temperature is 50.0 °C and whose pressure is 202 kPa. 6. How many moles of gas are contained in a 50.0 L cylinder at a pressure of 10100 kPa and a temperature of 35.0 °C? 7. Determine the number of grams of carbon dioxide in a 450.6 mL tank at 1.80 atm and minus 50.5 °C.
Given that 11.40 cm3 of K2Cr2O7 was required for complete oxidation, a) Calculate the numbers of moles of Cr2O7- used. b) Calculate the number of moles of Sn2+ that react with Cl2. c) Calculate the concentration of Cl2 in bleach. 5. Pyrolusite is a manganese ore containing mainly manganese (IV) oxide, MnO2.
Maximum absorbance occur when mole fraction of ligand is 0.65. [pic] = [pic] = [pic] = [pic] = [pic] mole fraction of metal ion : mole fraction of ligand = 1 : 2 ≈ 1 : 2 Therefore, formula of the complex: [Cu(en)2]2 Table 2 |Solution |Color Of Solution |Absorbance |Mole Fraction of Ligand | |1 |Very Light blue |0.224 |[pic] = 0.30 | |2 |Lighter blue |0.280 |[pic] = 0.40 | |3 |Light blue |0.420 |[pic] = 0.45 | |4 |Blue
CHAPTER 10 - Radioactivity and Nuclear Processes Composition of atomic nucleus - neutrons and protons Nuclides are nucleus of different isotopes, which is represented by the symbol [pic]X - X being symbol of the element. A is the mass number, which is the sum of number of protons & neutrons; Z is the atomic number, the number of protons, which also represents the nuclear charge. Number of neutrons = (A – Z). For example, the symbol of carbon-14 nuclide is [pic]C, which means a carbon-14 nuclide has 6 protons and 8 neutrons. The nuclide symbol of lead-206 is [pic]Pb.
The charge on a mole of electrons for some time and is the constant called the Faraday. The estimate of the value of a faraday is 96,485.3383 coulombs per mole of electrons. The estimate of the charge on an election base is 1.60217653 x 10^-19 coulombs per electron. Divided the charge of a mole of an election obtains the value of 6.02214154 x 10^23 particles per mole. According to Bender oxygen and hydrogen are elements other than carbon used to define mole.
Which compound has the greatest percentage by mass of Magnesium? a) MgCl2 : * MgCl2 = 24.31g + (2* 35.45g) = 95.21g Percentage by mass of Mg: * (24.31g/ 95.21g )* 100= 25.53 % b) Mg(NO3)2 : * Mg(NO3)2 = 24.31g + 2* (14.01g+(16.00g*3)) = 148.33g Percentage by mass of Mg: * ( 24.31g/ 148.33g) * 100 = 16.39% c) Mg3(PO4)2 : * Mg3(PO4)2 = (24.31g *3) + 2( 30.97g + (16.00g * 4)) = 262.87g Percentage by mass of Mg: * ( 72.93g/ 262.87g) * 100 = 27.74% d) MgSO4 : * MgSO4 = 24.31g + 32.07g + (16.00g * 4) = 120.38g Percentage by mass of Mg: * (24.31g/ 120.38g) * 100 = 20.19% The compound has the greatest percentage by mass of Magnesium is Mg3(PO4)2 3. Magnesium sulfide is 43.1 % Mg by mass. How many tons of Sulfur can be produced by the thermal decomposition of 20.5 tons of magnesium sulfide? Lab 4 Objective: The goal of the experiment is to find the mass of
NaCl 1 Na+ and 1 Cl- are formed). Calculate the osmolarity of that solution. What is the molar concentration of ALL particles? e.g. 0.15 M NaCl solution = 0.15 moles of Na+ atoms + 0.15 moles of Cl- atoms = 0.30 Osmoles In other words, the solution is said to have an osmolarity of 0.30 Osm (or 300 mOsm) Assume the osmolarity of the ICF of body cells to be 0.300 Osm (300 mOsm) 2nd, determine if the solute is a PENETRATING particle or is NON-PENETRATING.
Gallium, indium, aluminium, boron. Indium, gallium, aluminium, boron. JSC 2006, Physical Science [Turn over 2 5 The combination of protons, neutrons and electrons for a neutral atom of magnesium, 24 Mg, is: protons electrons A 10 14 11 B 11 13 12 C 12 12 12 D 6 neutrons 12 12 10 Which structure represents an atom of the noble gas in the first period. e e e pn np np pn n np p e e e e e e A 7 e e e pnn pnn npp e B C e e e D A mixture containing a soluble salt, sand and iron filings, can be separated into its components using techniques: R: use of