Predict the number of valence electrons for a chlorine atom. a. 1 b. 5 c. 7 d. 17 e. 35 Ionization Energy 59. Which of the following is a general trend for the ionization energy of elements in the periodic table?
The center-most part of an atom where the protons and neutrons 5. The weighted average mass of an element’s isotopes of that element 4. The smallest particle of an element that retains the properties 3. High-energy radiation that has no charge and no mass of neutrons 2. Atoms with the same number of protons but different numbers 1.
high melting point, hard, brittle, slightly soluble in water, conductor of electricity when melted or in solution Molecular solid - crystalline solid that has molecules arranged in a particular configuration. low melting point, generally insoluble in water, nonconductor of electricity. Metallic solid - crystalline solid that has atoms of metals arranged in a definite pattern. low to high melting point, malleable, ductile, conductor of electricity, insoluble in most solvents. Lesson 13.6 Changes of physical state: * necessary to draw a temperature-energy graph to see the change in temperature with a constant application of heat Heat of fusion - the amount of heat required to melt 1.00 g of substance.
Co-60 has a half-life of 5.3 years and can be used in a chemically inert form held inside a sealed container. This enables the equipment to have a long lifetime and not require regular maintenance. Tc-99m is used in over half of the current nuclear medicine procedures, such as pinpointing brain tumors. Tc-99m can be changed to a number of oxidation states. This enables production of a wide range of biologically active chemicals.
Bonding Formal Lab Introduction (with Background information): Any substance, whether it is a metal or nonmetal, people can determine it by seeing if it is shiny, soft, or reactive. Metals are shiny, reactive, and have high melting points, while nonmetals are soft, have low melting points and not very reactive, and that is how anyone can determine whether a substance is a metal or a nonmetal. Covalent bonding is when two atoms share electrons, but it only occurs in two nonmetals only. They have low melting points and they are not soluble. Although, Ionic bonding is when an atom gives away elections to another atom, which only happens in a metal and a nonmetal, and they have high melting points and are soluble.
4) When naming an ionic compound, which ion is given first? The metal ion is named first 5) Give explanations for the following: a. Argon will not react with any other element It already has a complete number of eight, a full number in its valance shell so it cannot react with itself or another element b. The reaction between sodium chloride gives out a lot of heat and light. The chemical energy of the product is less then the chemical energy of the reactants. This energy is indestructible and is converted to light and heat.
Rodan-222, a radioactive isotope sometimes fund in people’s basements has half-life of then 4 days. The shorter the half-life, the active appearing the atom is. For example, a test tube containing a gram of Rn-222 will cause a Geiger counter to click a raster rate then a gram of U- 238 because more atoms are changing per second. In our lab we will calculate the half-life of Ba-137m. This metastable radioactive isotope has a half-life of less than 5 minutes and is made from the radioactive decay of Cs-137 in a mini-isotope generator.
A central atom with 4 electron pairs (single bonds and/or lone pairs of electrons) could have which of the following molecular geometries? I. Trigonal bipyramidal II. Tetrahedral III. Trigonal pyramidal IV. Bent A. I and II B. II and III C. II, III, and IV D. I and IV E. I, II, and IV 65.
Explain how metallic bonding gives metals their unique properties. ________________________________________________________________ ________________________________________________________________ 9. Describe how covalent and ionic bonds differ with regard to melting point, boiling point, and bond strength. ________________________________________________________________ ________________________________________________________________ 10. Explain the difference between polar covalent and nonpolar covalent bonds.
When atoms bond together they share or transfer electrons to achieve a more stable electron arrangement, often a full outer main level of electrons, like the noble gases. There are three types of strong chemical bonds: 1.__ionic______, 2.____covalent____ and metallic IONIC bonding • Ionic bonding occurs between metals and non-metals • Metal atoms 3. ___lose___ electrons • Non-metal atoms gain electrons • Positive and negative ions are formed Sodium chloride has ionic bonding. [pic] • The sodium ion is positively charged because it has lost a negative electron