Inorganic Chemistry Questions

TUTOR Empirical Formulas. weight percents relative moles of each element mole ratios of the elements empirical formula Step 1 Assume 100 g of sample. The mass percent of each element can therefore be used as a mass, in grams. Calculate the amount of C present (in moles) in the 100-g of sample. Calculate the amount of H present (in moles) in the 100-g of sample. Calculate the mass precent of O by difference. %0 = 100 (%C + %H) Use this to calculate the amount of O present (in moles) in the 100-g of sample. Step 2 Compare the amounts (in moles) of the three elements. Calculate mole ratios by dividing the amount (mol) of each by the amount (mol) of the element present in the smallest amount. Step 3 Use the mole ratios to determine the empirical formula. The relative amounts (mol) present correspond with the relative number of atoms in the formula. If the ratios are not integers, convert them into improper fractions. For example, 1.5 becomes 1 1/2 and then 3/2. Likewise, 2.33 becomes 2 1/3 and 7/3. Similarly, 1.6 would be 1 3/5, or 8/5. Then the numerators and denominators of the fractions give relative whole numbers of atoms. For example, 2 1/3 is 7/3, which gives a ratio of atoms of 7 to 3. An alcohol is 70.57 % C and 5.935 % H by mass. The rest is oxygen. What is the empirical formula of the alcohol? Enter the elements in the order C, H, and then O.

1. What is the role of the manganese (IV) oxide (MnO) in this reaction 2. Write a reaction equation for the decomposition of hydrogen peroxide to produce oxygen 3. Why is the oxygen collection jar (the container in this case) filled with water before collecting the oxygen?

2. During the mid-20th Century, crackers were often stored in special tin containers that included a glass vial in their lids. The glass vial contained a dehydrated hydrate that would absorb moisture from the air as it rehydrated in order to keep the crackers from going stale. The most commonly used hydrate was epsom salts but they also included an additional hydrate like cobalt (II) chloride that would change colors as it went from being dehydrated to hydrated. When you heat the vial the water in the salts evaporates, so the cracker keeper can work again. I Why do you think that an indicator like cobalt (II) chloride was included in the vial?

An 8 oz glass of water contains 13.13 mol of water. How many molecules of water are in the glass? 7.91 x 10^24 molecules 2.18 x 10^-23 molecules 4.82 x 10^24 molecules 6.02 x 10^23 molecules

At 570. mm Hg and 25 °C, a gas sample has a volume of 2270 mL. What is the final pressure (in mmHg) at a volume of 1250 mL and a temperature of 175 °C?

Arrange the following bonds from the least polar to the most polar bond: N-F, Na-F, As-F, P-F, F-F WHERE ARE WE GOING? What information do we need to arrange the bonds from the least polar to the most polar bond? (Select all that apply.) the given bonds in the problem the atomic size of each element the Pauling electronegativity values the molar mass of each element the number of electrons for each element

The yellow dye, tartrazine, has been implicated in which one of the following health problems? cancer of the pancreas allergy stomach cancer None of these options is correct. liver cancer hypertension

Consider a burning candle. Reactants are the chemicals that are present before a reaction occurs while the products are the chemicals that are made by the reaction. Which of the following is true? (MARK ALL THAT APPLY) The reactants are more chemically stable than the products. The reactants have less stored energy than the products. The reactants are less chemically stable than the products. Less energy is required to start the reaction than is released by the reaction itself. The ore stored energy a substance has the more chemically stable it is. The reactants have more stored energy than the products. The more stored energy a substance has the less chemically stable it is. More energy is required to start the reaction than is released by the reaction itself.

An aqueous solution of Fe(SCN)2+ is red because A. the complex adds red radiation to the solvent. B. the complex absorbs the green component from the incoming white radiation and transmits the red component. C. the solution absorbs the red component of the incoming white radiation. D. the green component, which is the complementary color of red, of the incoming white radiation is transmitted.

The daily dose of ampicillin is 115 mg/kg of body weight. If you give 1.525 g of ampicillin to a patient, what is the patient's weight in pounds? (2.2 pounds = 1 kg). Use 4 significant figures in your answer.

2. Suggest a reason why it is desirable to use an excess of barium ion in the precipitation.

Low-density lipoprotein (LDL) is a type of cholesterol that is often known as "bad cholesterol". Find the volume (cm³) of 0.815 g of LDL if the density is 0.767 g/cm³.

A 170 g sample of a metal was placed into a graduated cylinder containing 75.4 mL of water. The volume of water rose to 98.3 mL. Find the density (g/ml) of the metal

12.. Before performing the vacuum filtration, one should check that the hoses are _____ walled or they will collapse; that the filtering flask is _____ (to be able to recover the sample if it goes through with the mother liquor, and free of or it may shatter when the vacuum is applied,

When using magnetic marbles to represent bonding atoms, what represents the "system"? The stationary marble The ruler The collision between the marbles The force of attraction between the marbles The moving marble

What is the correct net ionic equation, including all coefficients, charges, and phases, for the following set of reactants? Assume that the contribution of protons from H₂SO4 is near 100 %. Ba(OH)2 (aq) + H₂SO4 (aq) →

A sealed chamber contains an equilibrium mixture of NO₂ and N₂O4 at 300 °C. The partial pressures of NO2 and N2O4 are 1.8 and 24.1 atm, respectively. What is the value of Kp for the dimerization of NO2 2 NO₂(g) = N2O4(g), at 300 °C?

A chemist prepares a solution of sodium hyposulfate (Na2S2O3) by weighing out 42.9 kg of sodium hyposulfate into a 100. mL volumetric flask and filling the flask to the mark with water. Calculate the concentration in g/L of the chemist's sodium hyposulfate solution. Round your answer to 3 significant digits.

What is the total volume of gaseous products formed when 25.9 liters of butane (C4H10) react completely according to the following reaction? (All gases are at the same temperature and pressure.) butane (C4H10) (g) + oxygen (g) carbon dioxide (g) + water(g) _____ liters products

CuSO4(aq.) + KCN (excess)→→→→ complex of Cu. Among the following statements. (a) Oxidation states of Cu is +2 (b) The complex is colourless (c) The complex is water soluble (d) The complex is square planar The correct statement(s) is/are a, b, c only b, c only b, c, d only a, b, d only

What volume of bromine trifluoride is required to produce 63.5 liters of fluorine gas according to the following reaction? (All gases are at the same temperature and pressure.) bromine trifluoride (g) → bromine (g) + fluorine(g) _____ liters bromine trifluoride

Infrared radiation has frequencies from 3.0x10^11 to 3.0x10^14 Hz, whereas the frequency region for ultraviolet radiation is 3.0x10^15 to 3.0x10^16 Hz. We can say that: 1. The speed of infrared radiation is _____ ultraviolet radiation. 2. The wavelength of infrared radiation is _____ ultraviolet radiation.

Among the given statements : (1) Hypophosphoric acid has two P = O bonds. (2) Pyrophosphorous acid has two P-O-H bonds. (3) Phosphorous acid can undergo oxidation as well as reduction when heated (4) Pyrosulphurous acid has one S-O-S bond. The correct statements are: 1 and 2 only All of the above 3 and 4 only 1, 2 and 3 only

At 700 K the equilibrium constant Kc for the reaction between NO(g) and O₂(g) forming NO₂(g) is 8.7 x 106. The rate constant for the reverse reaction at this temperature is 0.54 M-¹s 1. What is the value of the rate constant for the forward reaction at 700 K?

Fill in the orbital energy diagram for the fluorine atom.

A perfect cube of aluminum metal was found to weigh 37.4 g. The density of aluminum is 2.70 g/mL. What are the dimensions of the cube? Show all calculations and how you derived the answer.

Which of the following occurs as the wavelength of a photon increases? The frequency decreases. The speed decreases. Planck's constant increases. The energy increases. None of the above occurs as the wavelength of a photon increases.

Select the incorrect statement among following: Ce4+ can act as good oxidizing agent Fe3+ / Fe2+ redox couple has more positive electrode potential than Mn3+/Mn2+ couple. Of the d4 species Cr2+ is strongly reducing while manganese(III) is strongly oxidising. Cobalt(II) is stable in aqueous solution but in the presence of strong field i.e. CN and NO2- complexing reagents it is easily oxidised.

For the following electron-transfer reaction: Al(s) + 3Fe3+ (aq) → Al3+ (aq) + 3Fe2+ (aq) The oxidation half-reaction is: The reduction half-reaction is:

In the laboratory you are given the task of separating Ag+ and Co2+ ions in aqueous solution. For each reagent listed below indicate if it can be used to separate the ions. Type "Y" for yes or "N" for no. If the reagent CAN be used to separate the ions, give the formula of the precipitate. If it cannot, type "No"

A student placed a sample of a food coloring that contains a mixture of a blue dye and a red dye at the top of a chromatography column filled with a nonpolar stationary phase. When water is poured through the column, two bands of colors are seen in the column, as shown in the diagram above. A student collects a sample of the blue dye from the column in a cuvette. Which of the following is least useful to determine the concentration of the sample using a spectrophotometer set at 640 nm? The volume of the sample The path length of the cuvette The absorbance of the dye at 640 nm The molar absorptivity of the dye at 640 pm

A 0.4419 g sample of a pure soluble chloride compound is dissolved in water, and all of the chloride ion is precipitated as AgCl by the addition of an excess of silver nitrate. The mass of the resulting AgCl is found to be 0.6082 g. What is the mass percentage of chlorine in the original compound? %

A student determines the iron (II) content of a solution by first precipitating it as iron(II) hydroxide, and then decomposing the hydroxide to iron(II) oxide by heating. How many grams of iron(II) oxide should the student obtain if her solution contains 58.0 mL of 0.540 M iron (II) nitrate?

What does the following equation represent? Ca5(PO4)3OH -----> 5 Ca²+ + 3 PO4³-+ OH* the production of calcium ions in milk. the production of phosphate in soft drinks. the formation of base (OH-) in cheese production. coral formation. the loss of bone material. None of these options is correct.

The transition metal complex(es) with zero magnetic moment, zero dipole moment and CFSE of -2.4 Δ0 is(are) (I) [Mn(CO)5(CH3)] (II) [trans-Ni(ethylene diamine)2Cl2] (III) [trans-Co(CN)4(NH3)2]- (IV) [trans-Fe(CN)4(CO)2]2- II, III III, IV I, III II, III, IV

Balanced chemical equation 2 C8H18(g) + 25 O2(g) →16 CO2(g) + 18 H2O(g) After the reaction, how much octane is left? Express your answer with the appropriate units. moles of C8H18 remaining =

Balanced chemical equation 2 Cs H18 (g) + 25 O2 (g)→16 CO2 (g) +18 H₂O(g) How many moles of water are produced in this reaction?

The fuel used in many disposable lighters is liquid butane, C4H10. How many carbon atoms are in 4.00 g of butane? Express your answer numerically in atoms.

Which of the following aspects of fructose activity in the body is correct? Since fructose is a sugar, it is metabolized in the same way as is glucose. Fructose is processed by the liver to make carbon monoxide and water. None of these options is correct. Fructose is processed by the liver to make fat. Fructose is not involved with the promotion of Advanced Glycation End products. Fructose can not be digested by humans because they lack the enzyme to break it down.

Glycation is a process which contributes to an enhanced sex drive due to increased absorption of tryptophan. process which links protein chains with simple sugars. process which contributes to a decreased sex drive due to increased absorption of tryptophan. None of these options is correct. positively charged amino acid. method of describing what happens when the white of an egg solidifies.

Calculate the mass of 1.00 x 10^24 (a septillion) molecules of water. Express the answer numerically in grams.

Metal M is a light-red metal, which is soft, malleable, and ductile. It melts at 1038°C. Because of its positive standard electrode potential it is insoluble in hydrochloric acid and in dilute sulphuric acid, although in the presence of oxygen some dissolution might take place. Medium-concentrated nitric acid (8M) dissolves metal readily. If coloured solution MSO4 obtained by dissolving metal in conc. H2SO4 is diluted & treated by KI excess, precipitate of metal(I) iodide is formed, which is white, but the solution is intensely brown because of the formation of triiodide ions. Select CORRECT regarding above information. If a clean iron nail or a blade of a penknife is immersed in a solution of a metal salt, a red deposit of metal is obtained Metal salt solution of "M" shows redox reaction with Na2S2O3 Solution obtained by reaction of metal "M" & AgNO3aq produce colorless solution with excess NH4OH Oxide of metal M (i.e. MO) dissolves in dil. HCI but not in excess KOH

The molecular formula mass of this compound is 180 amu. What are the subscripts in the actual molecular formula? Enter the subscripts for C, H, and O, respectively, separated by commas (e.g., 5, 6, 7).

Dolomite is a substance sold in health food stores. Select the correct statement. Due to the toxic nature of dolomite, it has been banned in the U.S. and Canada. Dolomite can contain toxic heavy metals such as mercury. Dolomite is a mixture of calcium and magnesium carbonate and is always purified to eliminate other elements. This product is mainly magnesium sulfate and is soluble in water. This substance is not a good source of calcium as it does not dissolve well in water. None of these statements is correct.

When aqueous solutions of sodium acetate and hydroiodic acid are mixed, an aqueous solution of sodium iodide and acetic acid results. Write the net ionic equation for the reaction. Use the solubility rules provided in the OWL Preparation Page to determine the solubility of compounds. Use H+ for the hydronium ion, CH3COOH for acetic acid and CH3COO¯ for the acetate ion. Be sure to specify states such as (aq) or (s) in your answers.

Hot dogs are mostly protein, fat and water. After removing the water from a hot dog it weighs 100 grams. The label says "80% fat-free" by weight. How many calories come from fat? 720 calories 320 calories 180 calories 900 calories 90 calories None of these options is correct.

Which one of the following is correct concerning flaxseed? It contains lignans which have possible anti-cancer effects. It is low in fiber. None of these statements is correct. It is not safe for human consumption. It contains only omega-6 fats. It has a constipating effect.

Identify the correct order for solubility of 2nd group. Solubility of oxalates increases from Ca to Ba Solubility of fluorides decreases from Ca to Ba Solubility of hydroxides increases from Ca to Ba Solubility of carbonates decrease from Ca to Ba

Give the number of significant figures for each of the following results. a. The length of the candle is 5.05 inches. b. The sample only weighs 0.0060 g on the electronic scale. c. The scientist measures the rate to be 8.010×102 meters/second. HOW DO WE GET THERE? Determine the number of significant figures in the following result: The length of the candle is 5.05 inches. Number of significant figures =

Classify the following as a mixture or pure substance. a The vegetable soup you had for lunch. mixture pure substance b The salt you sprinkle on your French fries. Omixture pure substance C The fertilizer your dad spreads on the front lawn in the spring. mixture pure substance d The hydrogen peroxide you cleaned a cut finger with. mixture pure substance