Classification of Elements and Periodicity Questions and Answers

The chemical functional group cyano (CN) is an extremely toxic chemical due to how it binds to the iron in our hemoglobin. When the chemical species is further reduced by two electrons, they are donated into a specific orbital in the MO diagram that changes its properties. Please draw the MO diagram for CN³- showing correct energy positioning for atomic and molecular orbitals. Please also calculate the bond order, and identify the HOMO and LUMO.

CIO4- + H₂S ---> CIO3- +S+ H₂O In the above redox reaction, use oxidation numbers to identify the element oxidized, the element reduced, the oxidizing agent and the reducing agent. name of the element oxidized: formula of the oxidizing agent: name of the element reduced: formula of the reducing agent:

2Cr³+ + 3Cu²+ + 7H₂O ---> 3Cu + Cr₂O72- + 14H+ In the above redox reaction, use oxidation numbers to identify the element oxidized, the element reduced, the oxidizing agent and the reducing agent. name of the element oxidized: formula of the oxidizing agent: name of the element reduced: formula of the reducing agent:

How does an increase in reactant concentration increase the rate of a chemical reaction? it does not increase the rate of the reaction it increases the frequency of collisions of reactant molecules it increases the energy of the collisions it provides a new reaction path with a lower activation energy

What are the units for heat capacity and specific heat? Heat capacity: kJ/°C Specific Heat: kJ/g °C Heat capacity: kJ/g°C Specific Heat: kJ/g Heat capacity: g/kJ Specific Heat: g°C/kJ Heat capacity: g°C/kJ Specific Heat: g/kJ

A theoretical chemist is inspired by the completion of the periodic table and the naming of element 118, Oganesson (Og). The scientist predicts that there could exist element 119. Complete the following sentences based on the characteristics an element with this atomic number would have. Predicted element 119 would be classified as This element would have _ reactivity. This element's atomic radius would be _ other elements in the same family This element's ionization energy would be _ other elements in the same family.

The chemical formula for calcium hydroxide is: Ca(OH)₂ Calculate the molar mass of calcium hydroxide. Round your answer to 2 decimal places.

The chemical formula for methanol is: CH3OH Calculate the molar mass of methanol. Round your answer to 2 decimal places.

Fill in the systematic names of the following chemical compounds. Note: for compounds containing hydrogen, you may give the common name instead.

Scientists can analyze metals using the emission spectrum produced when the sample is introduced into the flame of an emission spectrometer. The flame provides the energy to excite the electrons of the metal atoms to higher energy states. When the electrons return to the ground state, lines of characteristic wavelengths are produced. The lines in the emission spectrum are characteristic of the metal because each atom's ground-state electron configuration is unique. The emission line used for zinc determinations in atomic emission spectroscopy is 214 nm. If there are 9.00x10¹0 atoms of zinc emitting light in the instrument flame at any given instant, what energy (in joules) must the flame continuously supply to achieve this level of emission? Express your answer numerically in joules. During an emission, electrons move from a higher energy orbital to a lower energy orbital. Which of the following are valid transitions that produce lines in the emission spectrum of Zn?

Calculate the concentration of all ions present in each of the following solutions of strong electrolytes. a. 0.400 mole of Ca (NO3)2 in 300.0 mL of solution b. 1.5 moles of Na2SO4 in 2.00 L of solution c. 9.70 g of NH4Cl in 970.0 mL of solution d. 4.20 g of K3PO4 in 810.0 mL of solution

Write net ionic equations for the reaction, if any, that occurs when aqueous solutions of the following are mixed. (Be sure to specify states such as (aq) or (s). If a box is not needed, leave it blank. If no reaction occurs, leave all boxes blank and click on Submit.) a. iron(III) chloride and sodium hydroxide b. silver nitrate and ammonium selenate c. copper(II) sulfate and barium nitrat d. calcium nitrate and cesium iodide

In the laboratory you dissolve 24.3 g of potassium carbonate in a volumetric flask and add water to a total volume of 250 mL. What is the molarity of the solution? What is the concentration of the potassium cation? What is the concentration of the carbonate anion?

Diborane (B₂H6) is a gas at room temperature that forms explosive mixtures with air It reacts with oxygen according to the following equation B2H6(g) +302 (g) --> B2O3(s) + 3H₂O(l) How many grams of diborane will react with 8.0 mol of O₂? Express your answer to two significant figures and include the appropriate units.

A chemist prepares a solution of aluminum sulfate (Al₂(SO4)3) by measuring out 43.8 g of aluminum sulfate into a 100. mL volumetric flask and filling the flask to the mark with water. Calculate the concentration in mol/L of the chemist's aluminum sulfate solution. Round your answer to 3 significant digits.

In a beaker, 0.86 mol of potassium iodide and 0.52 mol of lead (II) nitrate are dissolved in water. A reaction occurs, and a white precipitate is observed. Calculate the mass (in grams) of the precipitate formed. Assume the reaction goes to completion. Do NOT include units in your answer. If you round during your calculation, be sure to keep at least three (3) decimal places. Report your answer to one (1) decimal place.

Give the "box notation" (also called the "dash notation") electron configuration of Ca by filling electrons into the orbital spaces provided. Press Check when complete.

Using NOBLE GAS notation write the electron configuration for the scandium atom.

Write the complete electron configuration for the helium atom. Using NOBLE GAS notation write the electron configuration for the beryllium atom.

What factors are required for a molecule to be polar? (Choose all that apply) The presence of polar covalent bonds are required. Polar bonds must be symetrically arranged around the central atom. Polar bonds must be assymetrically arranged around the central atom. There must be two or more polar bonds on the central atom. The central atom must have a non-bonding pair of electrons. The dipoles must add up to result in a net dipole.

Liquid hexane (CH₂(CH₂)4CH3) will react with gaseous oxygen (O₂) to produce gaseous carbon dioxide (CO₂) and gaseous water (H₂O). Suppose 6.9 g of hexane is mixed with 39.2 g of oxygen. Calculate the maximum mass of carbon dioxide that could be produced by the chemical reaction. Round your answer to 2 significant digits.

Write the complete electron configuration for the neon atom. Using NOBLE GAS notation write the electron configuration for the carbon atom.

Write the complete electron configuration for the sodium atom. Using NOBLE GAS notation write the electron configuration for the lithium atom.

The solubility rules are listed in table below. General Rules for Solubility of lonic Compounds (Salts) in Water at 25 °C. 1. Most nitrate (NO3) salts are soluble. 2. Most salts of Na+, K+, and NH4+ are [soluble. 3. Most chloride salts are soluble. Notable exceptions are AgCl, PbCl2, and Hg₂ Cl2. 4. Most sulfate salts are soluble. Notable exceptions are BaSO4, PbSO4, and CaSO4. 5. Most hydroxide compounds are only slightly soluble. The important exceptions are NaOH and KOH: Ba(OH)2 and Ca(OH)2 are only moderately soluble, 6. Most sulfide (S2), carbonate (CO32), and phosphate (PO4) salts are only slightly soluble." "The terms insoluble and slightly soluble really mean the same thing: such a tiny amount dissolves that it is not possible to detect it with the naked eye. On the basis of the general solubility rules, choose the substance that is not likely to be soluble in water. a. K₂SO3 PbSO3 Na₂SO3 C8₂SO3 b. BaF₂ CsF KF NaF C.KF CaF₂ NaF CsF

From the list below, choose which groups are part of the periodic table. metals acids flammable gases nonmetals semimetals ores conductors

Ammonium perchlorate (NH4CIO4) is a powerful solid rocket fuel, used in the Space Shuttle boosters. It decomposes into nitrogen (N₂) gas, chlorine (Cl₂) gas, oxygen (0₂) gas and water vapor, releasing a great deal of energy. Calculate the moles of oxygen produced by the reaction of 1.3 mol of ammonium perchlorate. Be sure your answer has a unit symbol, if necessary, and round it to 2 significant digits.

Adding base to pure water causes the [OH-] to equilibrium for water to shift in the direction toward the The shift causes the [H3O+] to [H3O+] x [OH-], which equals This added stress causes the and away from the in order to maintain the product

Consider the following unbalanced equation: C2H6(g)+Oz(g)→ CO2(g)+H2O(g) Which amount requires more oxygen gas, 2.43 mol C₂H6 or 28.8 g C₂H6? HOW DO WE GET THERE? For 2.43 mol C₂H6: What is the mole ratio between C₂H6 and O₂ in the balanced equation? 2C2H6(g) + 702(g) → 4CO2(g) + 6H₂O(g) X = Y = X mol O₂ Y mol C₂H6 mol O₂ mol C₂H6

Measurements show that unknown compound X has the following composition: element mass % nitrogen 26.0% oxygen 74.1% Write the empirical chemical formula of X.

What did Ernest Rutherford discover and what were there charges? He discovered the nucleus contained electrons. He discovered the nucleus contained protons. The electrons possessed a negative charge. The protons possessed a positive charge.

Which of the following are properties of alkali metals? mostly solids, dull, brittle reactive, conductors mostly solids, luster, high density, conductors mostly gases, brittle, dull, low density, insulators solids, luster, malleable, conductors, reactive

What is the electrostatic potential energy (in joules) between an electron and a proton that are separated by 45 pm?

Considering periodic trends, valence electrons in which of the following atoms experience the greatest effective nuclear charge (Zeff)? A) CI B) C C) F D) Ne E) B

Complete the table below. For example, in the first row decide whether Sc is a cation or anion. In the second row, write the symbol for the ion that an atom of cesium is mostly likely to form and then decide what type of ion it is.

The daily output of stomach acid (gastric juice) is 1000 mL to 2000 mL. Prior to a meal, stomach acid (HCl) typically has a pH of 1.42. (10.5, 10.6) a. What is the [H3O+] of stomach acid? b. One chewable tablet of the antacid Maalox contains 600. mg of CaCO3. Write the neutralization equation, and calculate the milliliters of stomach acid neutralized by two tablets of Maalox. c. The antacid milk of magnesia contains 400. mg of Mg(OH)2 per teaspoon. Write the neutralization equation, and calculate the number of milliliters of stomach acid neutralized by one tablespoon of milk of magnesia (one tablespoon = three teaspoons).

Which statement best describes the polarity of SCl4F₂? ► View Available Hint(s) The molecule is always polar. The molecule is always nonpolar. Depending on the arrangement of outer atoms, this molecule could be polar or nonpolar.

Which one of the following is the best scientific description of "burning calories"? Calories are removed from fats leaving carbon dioxide and water behind. None of these statements is correct. Fats, proteins or carbohydrates are converted into gases. Stored nutrients are converted into carbon dioxide and water accompanied by heat release. Calories in a solid form are converted to calories in a vapor form. Glycogen combines with carbon dioxide to yield oxygen.

Which one of the following concerning the genetically modified purple tomato is correct? It has been modified to have a higher content of lycopene. It was created by crossbreeding red tomatoes with plums. It has been modified to have a higher level of anthocyanins. It is only on the market in Canada. It has been modified to produce the Bt toxin. None of these statements is correct.

Which one of the following statements best describes why champagne is extremely bubbly? None of these responses is correct. Fermentation takes place in a closed bottle to retain the CO2 produced. After fermentation is completed, CO2 is added to a closed bottle. A secondary fermentation produced from sugar and yeast takes place in a closed bottle. Fermentation is started by adding CO2 to a closed bottle. Fermentation takes place in large vats and CO2 gas is then added to the wine.

After the final reaction in the copper cycle, the copper solid was rinsed with water and then ethanol. What was being removed from the copper in this process? The equation for the final reaction is given below. Would compounds from previous reactions (not this final reaction) also be removed? 3CuSO4 (aq) + 2Al(s) → 3Cu(s) + Al₂(SO4)3(aq)

The density of osmium (the densest metal) is 22.57 g/cm³. What volume would be occupied by 1.67 kg of osmium?

Alisha went to the doctor and got her blood calcium levels measured. If her blood calcium is 9.1 mg/dL. How many total grams of calcium are present in her bloodstream? (Alisha has a total blood volume of 3.7 L.)

Draw the Lewis dot structure for the compounds below. Determine the electronic structure and molecular geometry of those compounds by referring to their Lewis dot structures, the basics sheet provided and your text: a. oxygen difluoride (OF2): b. dinitrogen monoxide (N₂O): c. phosphorus trifluoride (PF3): d. formaldehyde (CH₂O): e. carbon tetrafluoride (CF4):

Your task is to write the chemical formula from each name on your work page. You should show some work to justify the answers but do not need to write a lengthy explanation. You will first match the name to the compound type and then write down the formula on your work page. > bartic acid maggoburnsic acid dinedogen pentaburnside homerium(III) nedtite milhouseum bartine 1. Acid 2. lonic compound 3. Molecular compound

Total number of CORRECT orders is :- (i) PbO₂ > PbO (oxidising strength) (ii) SiO₂ < NaCl (Melting point) (iii) Agl > AgCl (Colour intensity) (iv) ZnCl₂ < HgCl2 (Degree of ionisation in aqueous solution) (v) Na₂CO3 < MgCO3 (Temperature required for thermal decomposition)

No' and Ag' differ in Na2,CO3, is thermally stable while Ag,CO, decomposes into Ag2,O, CO2, and 02, Ag' forms complexes, Na' does not NaCl is water soluble, AgCl is insoluble NaCl and AgCl both give colour in flame when ignited

A compound is found to be 30.45% N and 69.55 % by mass. If 1.63 g of this compound occupy 389 mL at 0.00°C and 775 mm Hg, what is the molecular formula of the compound? N4O₂ NO₂ N₂O5 N₂O N₂O4

Given three cylinders containing O₂ gas at the same volume and pressure. Cylinder A is at -15°C, cylinder B is at -5°F, cylinder C is at 255 K. Which cylinder contains the largest mass of oxygen? cylinder A cylinder B cylinder C All cylinders contain the same mass of O₂.

What conditions trigger the release of ADH and what is ADH's mechanism of action? What conditions trigger the release of aldosterone and what is aldosterone's mechanism of action? Describe how the body compensate in a state of respiratory acidosis?

Watch this short video demonstration of the alkali metals reacting with water. Each of the metals react with water in the same way, shown here for sodium: 2 Na (s) + 2 H₂O (l) ---> H₂ (g) + 2 NaOH(aq) Explain what you observe in the video using your knowledge of electronic structure and periodic properties.