I expect the product's mass to be 400 grams. This belief stems from the law of conservation of mass, which states that mass can neither be created nor destroyed. In a sealed system, the mass of the reactants equals the mass of the products. Therefore, since the total mass of the reactants is 400 grams, the resulting mass of the products must also be 400 grams
OR
200
Among the listed options, the one indicating a chemical property is B. Water does not ignite, whereas gasoline is capable of burning. This distinction arises because both combustion and flammability are categorized as chemical properties.
extinction coefficient (ε) = 347 L·mol⁻¹·cm⁻¹. The chemical equation representing the reaction of chromium (Cr) with hydrochloric acid (HCl) is: 2 Cr + 6 HCl → 2 CrCl₃ + 3 H₂. To find the number of moles, we apply the formula: number of moles = mass / molar weight. For chromium, we calculate: number of moles of Cr = 0.3 × 10⁻³ (g) / 52 (g/mole), leading to number of moles of Cr = 5.77 × 10⁻⁶ moles. Examining the reaction, we observe that 2 moles of Cr yield 2 moles of CrCl₃, hence 5.77 × 10⁻⁶ moles of Cr will also produce 5.77 × 10⁻⁶ moles of CrCl₃. The molar concentration is determined by: molar concentration = number of moles / volume (L), thus molar concentration of CrCl₃ = 5.77 × 10⁻⁶ / 10 × 10⁻³, which equals 5.77 × 10⁻⁴ moles/L. To convert percent transmittance (%T) to absorbance (A), we use the equation A = 2 - log(%T). Therefore, A = 2 - log(62.5), leading to A = 0.2. The relationship defining absorbance (A) includes the extinction coefficient (ε), path length (l), and concentration (c): A = εlc, hence ε = A / lc, giving ε = 0.2 / (1 × 5.77 × 10⁻⁴), which results in ε = 0.0347 × 10⁴. Thus, the extinction coefficient is ε = 347 L·mol⁻¹·cm⁻¹.
According to the periodic table:
the molar mass of barium is 137.2 grams
the molar mass of oxygen is 16 grams
the molar mass of hydrogen is 1 gram
The molar mass of Ba(OH)2 can be calculated as 137.2 + 2(16) + 2(1) = 171.2 grams.
The molar mass of 4H2O is computed as 4 [2(1) + 16] = 72 grams.
Consequently, the molar mass of Ba(OH)2·4H2O is 171.2 + 72 = 243.2 grams.
Therefore, a sample weighing 243.2 grams of <span>barium hydroxide tetrahydrate includes 72 grams of water, meaning that within 92.8 grams, the mass of water would be:
mass of water in 92.8 grams = (92.8 x 72) / 243.2 = 27.474 grams.
Thus, when heating a 92.8 gram sample of Ba(OH)2·4H2O (barium hydroxide tetrahydrate), 27.474 grams of water will be emitted.</span>
