2. A feed ingredient gave the following percentage analysis moisture (16.0%), protein (18.0%), and fibers and minerals (66.0). If the moisture content were to be reduced by drying material in order to bring up the protein to 20.0%, what should be the final moisture content be?
3.A 1.367g sample of an organic compound was combusted in a stream of dry oxygen to yield 3.002g CO2 and 1.640 H2O. If the organic compound contained only C, H, and O. what its empirical formula?
4. How many molecules are there in 20.0g of benzene, C6H6.
5.Many crystalline compounds contain water of crystallization that is driven off when the compound is heated. The loss of weight in heating can be used to determine the formula. For example, a hydrate of barium chloride, BaCl2. H2O, weighing 1.222g is heated until all the combined water is expelled. The day power remaining weighs 1.042g. Compute the formula for the hydrate.
6. A 5.135g sample of impure limestone (CaCO3) yields 2.050g of CO2 when treated with an excess of acid. Assuming that limestone is only the component that would yield CO2, Calculate the percentage purity of the limestone sample.
7.A compound aluminum sulfate reacts with barium chloride.
a.) Give the chemical equation for the reaction.
b.)Balance the equation
2. To bring up the protein content from 18.0% to 20.0%, you need to calculate the amount of moisture that needs to be removed.
Step 1: Calculate the initial amount of moisture in the feed ingredient.
Initial moisture content = 16.0%
Weight of moisture = (16.0% / 100) × Initial weight
Step 2: Calculate the final amount of moisture after drying.
Final moisture content = ?
Final protein content = 20.0%
Weight of protein = (20.0% / 100) × Final weight
Step 3: Set up the equation using the principle of conservation of mass.
Initial weight of feed ingredient = Final weight of feed ingredient
(Weight of moisture + Weight of protein + Weight of fibers and minerals) = (Final moisture content + Weight of protein + Weight of fibers and minerals)
Step 4: Solve for the final moisture content.
Final moisture content = Initial weight - (Weight of protein + Weight of fibers and minerals)
3. To determine the empirical formula of the organic compound, you need to calculate the moles of each element.
Step 1: Calculate the moles of CO2 and H2O produced.
Moles of CO2 = (Mass of CO2 / Molar mass of CO2)
Moles of H2O = (Mass of H2O / Molar mass of H2O)
Step 2: Calculate the moles of C, H, and O in the organic compound using the stoichiometry of the combustion reaction.
Moles of C = Moles of CO2
Moles of H = (0.5 × Moles of H2O)
Moles of O = (Moles of H2O - Moles of H)
Step 3: Simplify the mole ratios to obtain the empirical formula.
Divide the moles of each element by the smallest number of moles obtained. Round the resulting ratios to the nearest whole number, and those whole numbers will give you the empirical formula.
4. To calculate the number of molecules in 20.0g of benzene (C6H6), you need to use Avogadro's number.
Step 1: Calculate the moles of benzene.
Moles of benzene = (Mass of benzene / Molar mass of benzene)
Step 2: Calculate the number of molecules using Avogadro's number.
Number of molecules = (Moles of benzene × Avogadro's number)
5. To determine the formula for the hydrate, you need to calculate the moles of each component.
Step 1: Calculate the moles of barium chloride.
Moles of barium chloride = (Mass of barium chloride / Molar mass of barium chloride)
Step 2: Calculate the moles of water expelled.
Moles of water expelled = (Initial mass - Final mass) / Molar mass of water
Step 3: Divide the moles of each component by the smallest number of moles obtained to obtain the formula for the hydrate.
6. To calculate the percentage purity of the limestone sample, you need to calculate the moles of CO2 produced.
Step 1: Calculate the moles of CO2.
Moles of CO2 = (Mass of CO2 / Molar mass of CO2)
Step 2: Calculate the moles of limestone present using the stoichiometry of the reaction.
Moles of limestone = Moles of CO2
Step 3: Calculate the percentage purity.
Percentage purity = (Moles of limestone / Initial moles of sample) × 100
7. a) The chemical equation for the reaction between aluminum sulfate and barium chloride is:
Al2(SO4)3 + 3BaCl2 -> 2AlCl3 + 3BaSO4
b) The equation is already balanced.
2. To find the final moisture content, we can use the given information and the assumption that the total percentage of the feed ingredient adds up to 100%.
First, let's calculate the percentage of fibers and minerals: 100% - (moisture percentage + protein percentage) = 100% - (16.0% + 18.0%) = 66.0%.
Since we need to reduce the moisture content by drying it, the new percentage of moisture can be calculated by subtracting the desired protein percentage from 100% (ignoring the fibers and minerals): 100% - 20.0% = 80.0%.
Therefore, the final moisture content should be 80.0%.
3. To determine the empirical formula of the organic compound, we need to calculate the molar ratios of the elements present.
First, we convert the given masses of CO2 and H2O to moles:
- Moles of CO2 = 3.002g / molar mass of CO2
- Moles of H2O = 1.640g / molar mass of H2O
Next, we calculate the moles of carbon, hydrogen, and oxygen present in the compound by multiplying the number of moles of CO2 and H2O by their respective ratios of carbon, hydrogen, and oxygen:
- Moles of carbon = Moles of CO2 * (1 carbon atom / 1 molecule of CO2)
- Moles of hydrogen = Moles of H2O * (2 hydrogen atoms / 1 molecule of H2O)
- Moles of oxygen = (2 * Moles of H2O) + Moles of CO2
Finally, simplify the ratio of moles of each element to get the empirical formula. If necessary, multiply the ratio by the smallest whole number to obtain the simplest whole-number ratio.
4. To find the number of molecules in 20.0g of benzene (C6H6), we need to convert the given mass of benzene into moles, and then use Avogadro's number to convert moles to molecules.
First, calculate the number of moles of benzene: 20.0g / molar mass of benzene.
Next, use Avogadro's number (6.022 x 10^23 molecules/mol) to convert the moles of benzene to molecules. Multiply the moles of benzene by Avogadro's number to get the number of molecules.
5. To compute the formula for the hydrate, we need to compare the weight loss from the expelled water to the weight of the remaining compound.
First, calculate the weight of the anhydrous compound (without water) by subtracting the weight loss of the expelled water (1.222g - 1.042g).
Next, calculate the molar mass of barium chloride (BaCl2) by summing the molar masses of its elements.
Then, divide the weight of the anhydrous compound (without water) by the molar mass of barium chloride to find the number of moles.
Finally, determine the ratio of moles of water to moles of barium chloride to determine the formula for the hydrate.
6. To calculate the percentage purity of the limestone sample, we need to find the amount of CO2 produced solely by the CaCO3 component.
First, calculate the moles of CO2 produced by dividing the given mass of CO2 (2.050g) by its molar mass.
Next, find the moles of CaCO3 present by dividing the moles of CO2 produced by the stoichiometric coefficient of CaCO3 in the balanced equation.
Finally, calculate the percentage purity of the limestone sample by dividing the moles of CaCO3 by the total moles of the sample (moles of CaCO3 / total moles of the sample) and multiplying by 100.
7.
a.) The chemical equation for the reaction between aluminum sulfate (Al2(SO4)3) and barium chloride (BaCl2) is:
Al2(SO4)3 + 3BaCl2 → 2AlCl3 + 3BaSO4
b.) Balancing the equation involves ensuring that the number of atoms is the same on both sides. In this case, there are two aluminum atoms on the left and two on the right, three sulfur atoms on the left and three on the right, 12 oxygen atoms on the left and 12 on the right, six chlorine atoms on the left and six on the right, and three barium atoms on the left and three on the right.
Thus, the balanced chemical equation is:
Al2(SO4)3 + 3BaCl2 → 2AlCl3 + 3BaSO4