To measure the amount of calcium carbonate (CaCO3) in a seashell, an analytical chemist crushes a 3.100 g sample of the shell to a fine powder and titrates to the endpoint with 120. ml. of 0.4500M hydrogen chloride (HCI) solution. The balanced chemical equation for the reaction is: 2HCl(aq) + CO (aq) → H₂CO3(aq) + 2Cl(aq) - What kind of reaction is this? If you said this was a precipitation reaction, enter the chemical formula of the precipitate. If you said this was an acid-base reaction, enter the chemical formula of the reactant that is acting as the base. If you said this was a redox reaction, enter the chemical symbol of the element that is oxidized Calculate the mass percent of CaCO, in the sample. Be sure your answer has the correct number of significant digits. Oprecipitation O acid-base Oredox 0 0 0 0% 7 X

Caps Tab Wall wen M Inbox (1.600)-ftantiudeledux Mail-Francesca A Tantillo-Out xEXP #12: Geometry-CHM150-2 x Aktiv Chemistry ← → C app.101edu.co 90°F Mostly sunny 1 D Q Z Uranium hexafluoride, UF, is an important compound used in the enrichment of uranium by gaseous diffusion. A A Graham's Law states that rate of effusion A/rate of effusion of B = (square root of Mass of B)/(square root of Mass of A). Calculate how fast 235 UF gas diffuses compared to 230UF. gas. Assume the temperature remains constant. 2 W S 3 E D # C $ 4 R OL F C ▷ll s FS % 5 T V C Question 19.c of 23 G P A 6 Y B H & 7 PrtScn N J 8 N Home 1 M ( 9 K End o O < 1 4 7 +/- PgUp 0 L times faster than 238UF 2 5 8 12 4 P 3 6 9 0 □ A PED PgOn 1924 G + 0 Update Submit C x 100 BE 5:22 PM 7/6/2022 Del Backspace 과

The great French chemist Antoine Lavoisier discovered the Law of Conservation of Mass in part by doing a famous experiment in 1775. In this experiment Lavoisier found that mercury(II) oxide, when heated, decomposed into liquid mercury and an invisible and previously unknown substance: oxygen gas. 1. Write a balanced chemical equation, including physical state symbols, for the decomposition of solid mercury(II) oxide (HgO) into liquid mercury and gaseous dioxygen. 2. Suppose 71.0 mL of dioxygen gas are produced by this reaction, at a temperature of 50.0 °C and pressure of exactly 1 atm. Calculate the mass of mercury(II) oxide that must have reacted. Be sure your answer has the correct number of significant digits.

요 Eto OEt 1. EtMgBr(xs) 2. H3O* HO

2 Automobile air bags inflate following a serious impact. The impact triggers the following chemical reaction. 2NaN3 (8)→ 2 Na(s) + 3N₂ (9) S W stry.com/myct/itemView?assignmentProblemID=213377858&attemptNo=2&offset=next X 7 # 3 E D 80 C $ 4 R 888 F V % 5 FS T Y G A Part A 6 B If an automobile air bag has a volume of 11.2 L, what mass of NaN3 (in g) is required to fully inflate the air bag upon impact? Assume STP conditions. IVE ΑΣΦ Provide Feedback m = Submit MacBook Air F6 Y H & 7 Request Answer N 40 U J * 8 @ C PwC FB I M ( 9 K DD ? O ) O g L command 3 F10 P . : ; Review I Constants I Periodic Table I { + [ option = 11 ? 1 I 323) Next > 1 delete

Part C F10 BO O 3.04 × 10³ 6.27 x 10-1 The dosage of quinine when a 145-lb adult takes a 200.-mg tablet is equivalent to ug drug per kg of body weight. ► View Available Hint(s) O 627 O 1.38 × 10³ P Pearson * Education Inc. All rights reserved. | Terms of Use Privacy Policy. Permissions Contact Us | Bb Home L End Insert ■ Review |- Constants | Periodic Table 1 2

Archimedes tells us the lifting power of a balloon (how much mass it can lift) is equal to the difference between the mass of the balloon and the mass of the air it displaces. That is, if the balloon occupies the same volume as 10 kg of air, but the balloon only weighs 2 kg, then the gas density kg 0.090 3 m H, balloon can lift 8 kg. Airships have sometimes been filled with hydrogen (H,), but hydrogen is very flammable, and kg 0.18 Не m after the Hindenburg caught fire and crashed in 1937 with serious loss of life airships have nearly always been filled with helium (He) instead. kg 1.23 3 m' air Suppose a new airship Star of Balogna will have the shape of a cylinder 100. m long, with a radius of 15.0 m, and will weigh 9400. kg without any gas inside it. Suppose also the average passenger weighs 81 kg. Calculate how many passengers the Balogna could carry if it were filled with hydrogen, and also if it were filled with helium. Passengers with H,: Passengers with He: