Guided Inquiry Activity 2 Bonding Model When At Least Two At

Guided Inquiry Activity 2bondingmodel 1when At Least Two Atoms Are J

Guided Inquiry Activity 2bondingmodel 1when At Least Two Atoms Are J

Guided Inquiry Activity #2 Bonding Model 1. When at least two atoms are joined together by bonds, a molecule is formed. A compound is formed from the bonding of atoms from at least two different elements. Figure 2.1 . Covalent and ionic bonds.

In the compound sodium chloride, the sodium cation is always carrying a positive charge (Na+) and the chloride anion is always carrying a negative charge (Cl-), but sometimes the compound will be represented as NaCl – without the charges explicitly shown – see Activity 1 for a review of this concept. 1. Define the word molecule using the words atoms and bond . 2. How many electrons would you expect between the C and O atoms joined with a double covalent bond (also called a “double bondâ) in Figure 2.1?

3. In the molecule glycine shown in figure 2.1, there are two different carbon atoms. The structure has been re-drawn below and the carbons labeled. a. How many bonds are being made with each of the two carbon atoms? i.e. How many bonds are being made with carbon 1; with carbon 2? b.

How many electrons are represented by the bonds surrounding each individual carbon atom? 4. The NaCl does not have a covalent bond – i.e. there is no sharing of electrons. – rather it has an ionic bond . What seems to be holding the NaCl (i.e. table salt) molecule together? Model 2.

Figure 2.2. Two representations of glycine Since food molecules are most often going to contain carbon, oxygen, nitrogen and hydrogen. The top rows of the periodic table are the most important when thinking about food. To determine the number of electrons that an atoms brings along when engaging in bonding, simply count from left to right. Starting on the left, count to the right along a single row – the position of the element on the P.T. within its row is equivalent to the number of electrons it brings along to bonding.

This “counting†strategy is synonymous with the Group Number for the column. For example, in the image of the Periodic table shown below, carbon is in Group IVB. The important number here being IV or “4â€. Carbon is in group 4 ; carbon is also four spaces in from the left in row 2 (also called period 2 ). Figure 2.3.

The “biochemical†periodic table[footnoteRef:0]. Elements in red are present in bulk form in living things and are essential for life. Since food is made of material from living things, those elements are the most important to the science of food and cooking. Those elements in yellow are trace elements that are very likely essential for life. Those elements in blue are present in some organisms and may be essential for life. [0: This Periodic Table comes from Concepts in Biochemistry by Rodney Boyer (published by Wiley)] Figure 2.4.

Counting electrons within a molecule. 5. In Figure 2.4, why is there only one electron in the blue box drawn around the hydrogen? Please include a reference to the periodic table in your answer 6. How many electrons are inside the box drawn around the oxygen in Figure 2.4?

How is this consistent with oxygen’s group number on the periodic table? 7. Based on the pattern of box drawing shown in Figure 2.4, how are lone pairs allocated when “assigning†electrons for the purposes of counting. 8. Complete the image below by drawing boxes around each atom in the molecule (using the drawing tool or inserting shapes) – include within the box electrons that “belong†to that atom.

Then complete the table that follows. Atom Number of electrons in the box Group number for that element on the periodic table (Figure 2.3) Number of covalent bonds formed with the atom Number (if any) of lone pairs on the atoms (electrons not in a bond) 1 (H) 2 (H) 3 (N) 4 (H) 5 (C) 6 (H) 7 (O) 8 (C) 9 (O) 10 (H) What is the relationship between number of bonds and lone pairs an atom forms/has to group number? Model 3. All living things (animals, plants microbes, and smaller life forms) are made of atoms and molecules. How those molecules are organized, interact and react are the building blocks for life.

Molecules are often divided into two categories, organic[footnoteRef:1] (those molecules containing carbon atoms) and inorganic molecules (everything else). Food molecules can also be held together with covalent bonds (typical of, but not exclusive to organic compounds ), ionic bonds (typical of, but not exclusive to inorganic compounds ) and mixtures of both types of bonds. [1: The word “organic†in this context has nothing do to with methods of farming or food production; it is a broad chemical concept that describes all molecules that are found in living things. Since the molecules of living things are largely based on carbon, a chemist would consider carbon compounds to be synonymous with organic compounds. ] Figure 2.5 .

Examples of organic and inorganic food molecules As we saw in Activity 1, an element with too few electrons carries a positive charge and is called a cation, while an element with too many electrons carries a negative charge and is called an anion. In Figure 2.5, we can see an example of this in citric acid vs. calcium citrate. In citric acid, all the oxygens are neutral, while in calcium citrate, some of the oxygen atoms are carrying a negative charge. Let’s examine this more closely in Figure 2.6 below. Figure 2.6.

The difference in electron number between a neutral and charged oxygen. Using the concept of the “electrons each atom brings along to bonding†developed in Model 2, the citric acid oxygen identified by the arrow in Figure 2.6 is bringing 6 electrons, while the comparable oxygen in citrate is bringing 7 electrons. It is the seventh electron that is extra ; it is giving that oxygen a negative charge. Remember that oxygen is in Group 6 of the periodic table. 9.

Study Figure 2.5. List below an example of a molecule that is held together with covalent bonds. Then also list an example of a molecule that is held together by ionic bonds. Then list an example of a molecule that is held together by both ionic bonds and covalent bonds. Then provide an example of a molecule that is organic and a molecule that is inorganic.

10. Calcium citrate is made with two citrate molecules and three Calcium ions . (An ion is an element that has too many or too few electrons, and is therefore carrying a charge). Why is this? (Hint: the overall molecule must be neutral) 11. In Figure 2.6, the extra electron present on the oxygen gives it a negative charge. a. Why are 6 electrons ok for an oxygen atom, but 7 is too many? b.

How many electrons would be too many for a nitrogen atom? c. How many electrons would be too few for a nitrogen atom? d. How does your answer to (c) explain the structure of ammonium chloride below? Why is the nitrogen carrying a positive charge? 12.

Table salt is an ionic compound – sodium chloride. Why might calcium citrate also be called the calcium salt of citric acid? Question 1 'Jenny Cochran, a graduate of The University of Tennessee with 4 years of experience as an equities analyst, was recently brought in as assistant to the chairman of the board of Computron Industries, a manufacturer of computer components. During the previous year, Computron had doubled its plant capacity, opened new sales offices outside its home territory, and launched an expensive advertising campaign. Cochran was assigned to evaluate the impact of the changes.

She began by gathering financial statements and other data. (Data Attached) a. What effect did the expansion have on sales and net income? What effect did the expansion have on the asset side of the balance sheet? What do you conclude from the statement of cash flows? b. What is Computron’s net operating profit after taxes (NOPAT)?

What are operating current assets? What are operating current liabilities? How much net operating working capital and total net operating capital does Computron have? c. What is Computron’s free cash flow (FCF)? What are Computron’s “net uses†of its FCF? d.

Calculate Computron’s return on invested capital (ROIC). Computron has a 10% cost of capital (WACC). What caused the decline in the ROIC? Was it due to operating profitability or capital utilization? Do you think Computron’s growth added value? e.

What is Computron's EVA? The cost of capital was 10% in both years. f. Assume that a corporation has $200,000 of taxable income from operations. What is the company's federal tax liability? g. Assume that you are in the 25% marginal tax bracket and that you have $50,000 to invest.

You have narrowed your investment choices down to municipal bonds yielding 7% or equally risky corporate bonds with a yield of 10%. Which one should you choose and why? At what marginal tax rate would you be indifferent? Question 2 James Madison was brought in as assistant to Computron’s chairman, who had the task of getting the company back into a sound financial position. Madison must prepare an analysis of where the company is now, what it must do to regain its financial health, and what actions to take.

Your assignment is to help her answer the following questions, using the recent and projected financial information shown next. Provide clear explanations, not yes or no answers. a. Why are ratios useful? What three groups use ratio analysis and for what reasons? b. Calculate the profit margin, operating profit margin, basic earning power (BEP), return on assets (ROA), and return on equity (ROE).

What can you say about these ratios? c. Calculate the inventory turnover, days sales outstanding (DSO), fixed assets turnover, operating capital requirement, and total assets turnover. How does Computron's utilization of assets stack up against other firms in its industry? d. Calculate the current and quick ratios based on the projected balance sheet and income statement data. What can you say about the company’s liquidity position and its trend? e.

Calculate the debt ratio, liabilities-to-assets ratio, times-interest-earned, and EBITDA coverage ratios. How does Computron compare with the industry with respect to financial leverage? What can you conclude from these ratios? f. Calculate the price/earnings ratio and market/book ratio. Do these ratios indicate that investors are expected to have a high or low opinion of the company? g.

Use the extended DuPont equation to provide a summary and overview of Computron's projected financial condition. What are the firm's major strengths and weaknesses? h. What are some potential problems and limitations of financial ratio analysis? i. What are some qualitative factors analysts should consider when evaluating a company’s likely future financial performance? Submit your answers in a Word document.

Paper For Above instruction

Understanding chemical bonding is fundamental to the study of chemistry and essential for analyzing molecular interactions in biological systems, food chemistry, and material science. Bonding models such as covalent and ionic bonds explain how atoms connect to form molecules and compounds, shaping the physical and chemical properties of substances. This paper explores the concepts of molecular bonding, electron sharing and transfer, and their relevance to food and biological molecules, emphasizing how these principles underpin vital processes in life and industry.

The term molecule is often defined as a group of atoms bonded together, representing the smallest unit of a chemical compound that retains its chemical properties. Atoms are held together by bonds—forces that allow the atoms to stay connected in specific arrangements. Covalent bonds involve the sharing of electron pairs between atoms, resulting in stable molecules, whereas ionic bonds involve the transfer of electrons from one atom to another, creating ions that attract each other through electrostatic forces. For instance, sodium chloride (NaCl) illustrates ionic bonding where sodium loses an electron to become Na⁺, and chloride gains an electron to become Cl⁻. The stability of ionic compounds arises from these electrostatic attractions rather than sharing electrons, as in covalent bonds.

Considering covalent bonding, the number of electrons shared between atoms is critical. For example, in carbon monoxide (CO), a double covalent bond entails sharing four electrons—two from each atom—resulting in a strong, stable double bond. In Figure 2.1, the double bond between C and O involves four electrons, which is typical for double covalent bonds. The distribution of electrons in bonds influences molecular stability and reactivity, impacting biochemical functions and food chemistry.

Focusing on biological molecules like glycine, an amino acid, the structure includes two different carbon atoms, each with specific bonding patterns. Carbon 1, bonded to amino and carboxyl groups, typically makes four bonds, including single bonds to nitrogen and hydrogen and a double bond to oxygen in the carboxyl group. Carbon 2, part of the side chain, forms three bonds—single bonds with other carbons or hydrogens. The bonds are represented by shared electrons, with each bond comprising a pair of electrons. These electrons are depicted through bonds surrounding each carbon atom. The number of bonds correlates with the atom's group number in the periodic table, reflecting its valence electrons. For example, carbon (group 4) forms four bonds, nitrogen (group 5) five bonds, and oxygen (group 6) two bonds with lone pairs, which are non-bonded electron pairs occupying valence orbitals.

Ionic and covalent bonds create diverse molecular structures essential for biological functions and food chemistry. Ionic bonds, such as in NaCl, are held together by electrostatic attractions rather than shared electrons. In biochemical contexts, the stability of molecules depends on how these bonds form and interact. Elements like oxygen, in Group 6, tend to accept two electrons to fulfill their octet, with lone pairs representing non-bonding electrons. For example, in water molecules, oxygen carries two lone pairs and forms two covalent bonds with hydrogen atoms. The electron counting method involves assigning electrons within boxes around atoms, considering lone pairs and bonding electrons, which aligns with their group number. For instance, in water, oxygen’s box contains eight electrons, matching its valence shell requirement.

Understanding molecular organization further extends to categorizing molecules as organic or inorganic. Organic molecules contain carbon, often forming covalent bonds with hydrogen, oxygen, nitrogen, and other elements. For example, amino acids, sugars, and lipids exemplify organic compounds, vital for life and food energy. In contrast, inorganic molecules, such as salts and minerals like calcium citrate, lack carbon-hydrogen frameworks but are crucial in metabolic processes. Calcium citrate, formed by combining calcium ions with citrate molecules, illustrates ionic interactions where calcium shares electrostatic attraction with negatively charged oxygen atoms. The electron count on oxygen in such molecules determines their charge; oxygen with six electrons is neutral, but with seven, it bears a negative charge, as observed in citrate.

In food chemistry, molecules are stabilized by covalent bonds (e.g., in glucose or amino acids), ionic bonds (e.g., in salts like calcium citrate), or both. The charge distribution on molecules influences their solubility, reactivity, and biological activity. For example, calcium citrate’s neutrality is achieved by balancing positive calcium ions with negatively charged citrate molecules. The excess electron on oxygen imparts a negative charge when oxygen exceeds its octet, which is consistent with oxygen’s group 6 status, where accepting two electrons completes its valence shell. For nitrogen, exceeding five electrons leads to instability, with six or more electrons associated with negative charges, explaining why ammonium ions, where nitrogen has a positive charge, accommodate additional protons.

Similarly, salts like NaCl are ionic compounds composed of sodium and chloride ions, with the overall neutrality maintained by electrostatic forces. The designation "calcium salt of citric acid" indicates that calcium ions are combined with citrate molecules, balancing charges to form a neutral compound. This structural understanding helps explain biological processes, food preservation, and the chemistry underlying mineral supplements, emphasizing the importance of electron count, bond types, and molecular organization in chemical stability and function.

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