Predict the number of valence electrons for a sulfur atom. a. 4 b. 6 c. 8 d. 16 e. 32 58. Predict the number of valence electrons for a chlorine atom.
Pb (NO3) 2 10. A compound is 42.3 % C, 5.94 % H, 32.9 % N, and 18.8 % O and has a molecular mass of 425.25 g/mol. Calculate the empirical and molecular formula. C15H25N10O5 11. How many moles of Al2O3 are produced by the reaction 200. g Al?
The fact that the energy needed to break the necessary bonds falls within the visible light spectrum is the basis on which the experiment is based. This brings up the issue of selectivity. For example, the bromine radical is more selective than the chlorine radical. This has to do with electronegativity. It is known that chlorine is more electronegative than bromine, and thus chlorine is more reactive, and less discriminatory as to what it will react with, thus making bromine more “selective”.
B) 15 protons. C) 15 electrons. D) 8 electrons in its outermost electron shell. E) B and C only 8) A covalent bond is likely to be polar when A) one of the atoms sharing electrons is much more electronegative than the other atom. B) the two atoms sharing electrons are equally electronegative.
O O O O O O O O I I I O O O O O O I O O O I I O The top three are equally important. The first two on the bottom are of equal importance. I think the bottom right two will be most important (fewer formal charges), then maybe the bottom left structure (maximize bonding), then the top three structures. The order of importance isn’t entirely clear between the last two groups. (Argument between maximize bonding and put negative charge on the more electronegative atom.)
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
Isotopes Lab By: Darlene Cortez (1st Pd) Background: Atoms of the same element that have different masses are known as isotopes. The difference in mass between isotopes is the result of these atoms having different numbers of neutrons. Key vocabulary: Relative abundance- Relative abundance is a component of biodiversity and refers to how common or rare a species is relative to other species in a defined location or community. Weighted average - An average that takes into account the proportional relevance of each component, rather than treating each component equally. Average Atomic Mass- The mass calculated by summing the masses of an elements isotopes, each multiplied by its natural abundance on earth Mass Number- The total
A molecular orbital is merely a Schrödinger orbital which includes several, but often only two nuclei. If this orbital is of type in which the electron(s) in the orbital have a higher probability of being between nuclei than elsewhere, the orbital will be a bonding orbital, and will tend to hold the nuclei together. If the electrons tend to be present in a molecular orbital in which they spend more time elsewhere than between the nuclei, the orbital will function as an anti-bonding orbital and will actually weaken the bond. Electrons in non-bonding orbitals tend to be in deep orbitals (nearly atomic orbitals) associated almost entirely with one nucleus or the other, and thus they spend equal time between nuclei or not. These electrons neither contribute nor detract from bond strength.
Post- Lab Questions 1a. Zinc shot was used to determine density instead of granular zinc beacause the small granules of zinc trapes air bubbles while zinc shot does not. Knowing this, will the measured volume of zinc in the form of granules be greater or smaller? Since zinc granules are known to trap air bubbles, the volume would be greater as these bubbles take up volume in the graduated cylinder. The zinc granules will provide unaccurate results.
1 / [CO2] C. [CaO][CO2] / [CaCO3] D. [CaCO3] / [CaO][CO2] _____ 13. The value of Kp for the reaction 2 NO2 (g) [pic] N2O4 (g) is 1.52 at 319 K. What is the value of Kp at this temperature for the reaction N2O4 (g) [pic] 2 NO2 (g) ? A. -1.52 B. 1.23 C. 5.74 X 10-4 D. 0.658 _____ 14.