in the nucleus of a given atom. The atomic number is the number of protons in an cesium scandium chromium ruthenium 13. Oxygen-18 12. Hydrogen-3 11. Hydrogen-1 Isotope 20 8 1 1 92 65Cu 29 235U 92 Chemistry:
Test #2 ANSWERS CHM 101 Part I Multiple Choice (2 points each) 1. Which element is most likely to form three covalent bonds? A) C B) Si C) P D) S E) Se 2. A chemical bond formed when two atoms share two pairs of electrons is a ________ bond; it is best described as ________. A) double; covalent B) double; ionic C) single; covalent D) single; ionic E) triple; covalent 3.
A. 1.99 x 10-25 B. 9.55 x 10-25 C. 6.62 x 1016 D. 1.51 x 10-17 E. 1.51 x 10-26 4. Of the following transitions in the Bohr hydrogen atom, the __________ transition results in the emission of the highest-energy photon. A. n = 3 n
Zinc ion and Iodine-iodide-triodide ion in water: It was a liquid solution in a bottle, it was very dark orange-brown color. Solid Zinc Iodide: A very white powdery substance that had several clumps within it. It was also very dry in nature. Mass Table Substance Amount of Mass Measured for Actual Mass Granular Zinc 2.0 grams 1.9 grams Iodine Crystals 2.0 grams 2.1 grams Observation of Reaction Shown below and Included within the lab notes on pages 12 and on page 14. Placing Acetic Acid in Zinc and Iodine test tube After placing the Acetic Acid in a normally unreactive test tube containing Zinc and Iodine, the solution changed to a more orange and then to a more red-brown color.
1. Observation: Granular zinc: metallic, grayish solid. Iodine chips: Dark purple colored, sparkly solid. Zinc and iodine reaction in deionized water: Formed cloudy precipitate of Zinc hydroxide. Also a very pale purple tint formed.
We resulted that lead, silver, and copper are the strongest oxidizing agents, and that magnesium and zinc are the weak oxidizing agents. The strong oxidizing agent oxidized the weak oxidizing agent and in turn the strong oxidizing agent got reduced while oxidizing the weak agent. When a reaction occurred, the solid metal reduced the ion, and in turn made it the more reactive metal. In part two we used a solvent extraction technique to derive an activity series for the halogens. With the use of this technique we placed chlorine, bromine, and iodine into solutions containing chloride, bromide, and iodide.
Neutrons, Protons and electrons are all sub-atomic particles. In relative mass, we always think of protons and neutrons in having a mass of 1 and electrons a mass of 1/1840, which shows that electrons are considerably smaller than protons and neutrons, and only make up a small part of the atom. The amount of protons and neutrons added together is the relative atomic mass, and this is the main structure of the atom. 2. The arrangement of particles in an atom Protons and neutrons make up the main, dense, central nucleus in the centre of the atom.
h) A way to make hard water softer is to put an sodium nitrate and create a precipitate to mellow out the reaction. Another way of making it softer is by removing the calcium ions one way of doing that is by boiling the solution to take out some of the ions. Conclusion: Overall, we determined that sodium carbonate, Na2CO3, is the anion that can be used to precipitate the most metal cations. Also, we learned that the anion sodium chloride, NaCl, could be used to remove silver ions from solutions. The stuff that I found interesting was that how many colours you can get when you mix the cations and anions
David Kemp OCR Chemistry A Unit 1: F321 Atomic Structure (a) describe protons, neutrons and electrons in terms of relative charge and relative mass; Proton +1 1 Neutron 0 1 Electron -1 1/2000 Relative Charge Relative Mass (b) describe the distribution of mass and charge Within an atom; Positively charged Nucleus containing most of the mass, surrounded by atomic shells with orbiting electrons of negative charge and negligible mass. (c) describe the contribution of protons and neutrons to the nucleus of an atom, in terms of atomic (proton) number and mass (nucleon) number. The atomic number of the nucleus, also the proton number, shows the number of protons in the nucleus. It also defines the element. The number of neutrons added to the number of protons is the nucleon number or mass number.
It is possible that fluorine can substitute for hydrogen in organic reactions. Fluorine has been known to form compounds with rare gases, including xenon, radon, and krypton. Free fluorine has a characteristic pungent odor, detectable at concentrations as low as 20 parts per billion. Both elemental fluorine and the fluoride ion are highly toxic. The recommended maximum allowable concentration for a daily 8-hour time-weighted exposure is 0.1 parts per million.