Search & Filtering
Aspirin (acetylsalicylic acid) is widely used to treat pain, fever, and inflammation. In COVID 19 treatment it is also given as a blood thinner to prevent blood clotting for patients showing very high D-dimer value.
It is produced from the reaction of salicylic acid with acetic anhydride with sulphuric acid as a protonating agent.
In an industry, 10.00 kg of salicylic acid is mixed with 10.00 kg of acetic anhydride.
a) Which reactant is limiting? Which is in excess?
b) What mass of excess reactant is left over?
c) What mass of aspirin is formed assuming 100% yield (Theoretical yield)?
d) What mass of aspirin is formed if the reaction yield is 70.0%?
a) Write the balanced equation for the reaction of acetic acid with aluminium hydroxide to form water and aluminium acetate:
b) Using the equation determine the mass of aluminium acetate that can be made if we start the reaction with 150 grams of acetic acid and 300 grams of aluminium hydroxide.
c) What is the limiting reagent?
d) How much of the excess reagent will be left over after the reaction is complete?
9. Two elements, Sodium and Chlorine, react to form crystals out of a water solution. What can be said about the space between the atoms in the crystal lattice?
A. The atoms pack so tightly that they completely flatten against each other
B. In between the atoms is air.
C. Water molecules get stuck in between the sodium and chlorine atoms.
D. There is nothing but space between the atoms in the crystal
2. Experiments have shown that carbon will bond with several different elements. Some examples are methane (CH4), Carbon Disulfide (CS2), Carbon Monoxide (CO). Which of the following answers best describes the Law of Multiple Proportions as it related to the bonding types in carbon as described above.
A. Carbon follows the Law of Multiple Proportions; it is demonstrated in the above example by bonding to different elements in 4:2:1 ratios in the above compounds.
B. Carbon follows the Law of Multiple Proportions; it is demonstrated by being able to bond to many different elements.
C. Carbon does not follow the Law of Multiple Proportions because in the given example, a ratio of 1:3 is missing.
D. Carbon does not follow the Law of Multiple Proportions solely based on the statement above; no examples are given where carbon bonds to the same element with different simple integer ratios.
The combustion of naphthalene (C10H8), which releases 5150.1kj/mol, is often use to calibrate calorimeters. A 1.05-g sample of naphthalene is burned in a calorimeter, producing a temperature rise of 3.86oC. Burning a 1.83-g sample of coal in the same calorimeter causes a temperature change of 4.90oC. What is the energy density of the coal?
- An ionic bond is typically formed when valence electrons are transferred between a… (2) A) Halogen and non-metal B) Non-metal and metalloid C) Metal and metalloid D) Metal and non-metal
- Bonding in hydrogen gas is an example of a… (2) A) Metallic bond B) Ionic bond C) Polar covalent bond D) Non-polar covalent bond 1.3 An atom with the highest electronegativity is… (2) A) Carbon B) Oxygen C) Chlorine D) Fluorine 1.4 A nucleophile is a… (2) A) Arrhenius acid B) Arrhenius base C) Lewis acid D) Lewis base 1.5 In contrast to a carbanion, a carbocation is… (2) A) An electrophile B) A Lewis acid C) Electron-deficient D) All of the above 1.6 An anti-clockwise circle in R/S designation corresponds to… (2) A) (R)-configuration B) (S)-configuration C) Both A and B D) None of the above
- 85.0 mL of a solution of NaOH is diluted to a final volume of 290.0 mL and the new molarity is 0.0500 M. Calculate the original molarity of the base.
M1*V1= M2*V2
How many grams of glucose (C6H12O6) are needed to prepare 100mL of a 5% glucose solution?
What is the precent by mass concentration of a solution that contains 5.03g of salt dissolved in 19.7g of water?
