Why do we need to cover the beaker with aluminum foil or saran wrap

Q: The partial pressure of oxygen is 0. 20 atm at sea level at 25°C. Calculate its partial pressure at…

A: The correct answer is given below

Q: A buffer with a pH of 4.21 contains 0.37 M of sodium benzoate and 0.36 M of benzoic acid. What is…

A: we have to calculate [H3O+] after addition of HCl to the buffer solution

Q: Curved arrows are used to illustrate the flow of electrons. Using the provided starting and product…

A: Alcohols when heated in the presence of small amount of acid undergo dehydration to give alkene.…

Q: What would a glassware assembly like this be used for? Heating a reaction under reflux conditions…

A: Fractional distillation is a process by which components in a chemical mixture are separated into…

Q: Which statement is NOT true regarding natural vs. synthetic materials? A) An example of a natural…

A: Generally substances or materials are devided as natural and synthetic.  Natural materials are those…

Q: Why do you think polymers have no definite melting point?

A: Here we have to predict why ploymer have no definite melting point.

Q: What happens when your stearic acid solution forms a bead or small film that does not spread on the…

A: When a stearic acid solution forms a bead or small film that does not spread on…

Q: Please help complete the sub-parts

A: The given answers for #(a), #(b) and #(c) are right.

Q: wer A small amount of HNO3(aq) is added to a solution of FeBr2 as well as to a solution of Fe(CN)2.…

A: The question is based on the concept of Le-chatlier principle.It States that when a system at…

Q: Pure aspirin has a melting point of 135-136 °C. Before the melting point was determined - if the…

A: Melting point is the temperature at which a substance changes from a solid to a liquid phase at…

Q: Where on the periodic table would you expect to find another element that could be used as an…

A: Answer -  n-type materials are generally differentiated using hot-point probes. This laboratory…

Q: Which type of model best represents crystals A:space-fill B:Lewis dot C:ball-and -stick D:ribbon

A: We are to discuss which type of model best represents crystals  from the given options. Space fill…

Q: formula Binary? Covalent or Polyatomic ion? Cation variable charge? What? Yes, Gold(II) Name ionic…

A: Since you have posted a question with multiple sub-parts, we will solve the first three sub-parts…

Q: Given these data, calculate the moisture content of the sample. Weight of empty container: 12.0156 g…

A: Moisture content - It is the quantity of water contained in a sample of soil, salt , wood or crops…

Q: If there is no physical change in the different materials that are combined together, __________ is…

A: Given statement is :  If there is no physical change in the different material that are combined…

Q: Adhesive forces occur between different molecules.

A: Adhesive forces is defined as the attraction between the two different substances like glass and…

Q: What are the uses of recrystallization, decolorization, and sublimation?  Give  examples of each.

A: Recrystallization is process of removing insoluble solid impurities from an organic compound. The…

Q: The average normal concentration of Ca2+ in urine is 5.33 g/L. a) Calculate the concentration of…

A: Solubility is defined as the maximum amount of solute which is able to dissolve in a solvent. Solute…

Q: A student ran a TCL plate with a three different molecules that have the same carbon structure but…

A: As we know in TLC we use silica gel as stationary phase.

Q: Hylon VII, a starch-based 'green' substitute for styrofoam packing material, has a bulk density of…

A:

Q: What is meant by Chemical Communication ?

A: Given: To define chemical communication

Q: Question for each of the following life cycle analysis (LCA), state two useful functional units that…

A:

Q: lonic Compounds and Ratios Chemistry When salt crystals of ionic compounds are dissolved by water…

A: For the first three solutions, anions are drawn as shown below.

Q: Question Completion Status: QUESTION 2 What is the formal charge on nitrogen in the following…

A: Applying formula of formal charge FC= V-N-B/2

Q: Sublimation is preferred over recrystallization when you work with an amount of solid material to be…

A: There are many purification techniques. Sublimation and recrystallization are purification…

Q: 39. A person claimed that his stomach ruptured when he took a teaspoonful of baking soda in a glass…

A: NaHCO3 + HCI ==> NaCI + H2O + CO2 1 mole NaHCO3 reacts to form 1 mole

Q: Choose an example of polymorphs. a.graphite and graphine b.diamond and adamant c.pyrite and gold…

A: Polymorphism is the ability of a substance to crystallize into different crystalline forms. These…

Q: Consider the pressure of a height of 10 km in a volume of air, M = 0.0289 kg/mol. If the pressure…

A: Solution - According to the question - Given values - P at T = 300 K P1 = 101.325 *exp (-0.0289 *…

Q: Glassware/Tool Do’s Donts 1. Stirring Rod     2. Glass Funnel     3. Wire Mesh     4. Mortar and…

A: Glassware refers to laboratory equipment made of glass, typically used in scientific experiments,…

Q: Draw the major product of this reaction. Ignore Ignore inorganic byproducts. stereochemistry.

A: Gilman reagent: Lithium organocuprates, R2CuLi is known as Gilman reagent.  Gilman reagent is very…

Q: A student sets up the following equation to convert a measurement. (The ? stands for a number the…

A: Conversion factors are factors that help to convert one form of the unit to another form of the…

Q: QUESTION 6 If the atmospheric pressure is 190 torr, what is the pressure of the enclosed gas in a…

A:

Q: What might be the formulation (what the manufacturer mixes with aspirin in making the tablet)…

A: Aspirin is used as pain killer. Following is the structure of aspirin.

Q: Which glass can cut off ultraviolet rays?

A: Glass is an amorphous solid. It is transparent in nature. There are many types of glasses and have…

Q: 1. Complete the table [H3O*] 3.5 x 10-3 [OH] pH pOH 3.8x10-7 1.8x10-9 7.15

A: Hi, since you have posted multiple questions we will answer the very first question for you. Kindly…

Q: A good sample of benzoic acid melts at 121-122˚C. However, a student had a sample that melted over a…

A: Given: A good sample of benzoic acid melts at 121-122˚C. However, a student had a sample that melted…

Q: At 300 K consider a colloidal solution, M = 150 kg/mol, in a gravity field. If the concentration of…

A: Temperature = 300K Mol mass = M = 150kg/mol Colloid concentration at top = Mtop = 0.0008M Colloid…

Q: Part A: Multiple Choice Identify the letter of the choice that best completes the statement or…

A: 1). Tin is in +4 oxidation state, therefore Total 50 protons, (120-50 = 70) neutrons,  46electrons .…

Q: Can two samples that have different sets of chemical elements be the same mineral? Why or why not?…

A: A substance is referred to as a mineral if it is an inorganic, homogenous, crystalline solid that…

Q: Calculate the approximate length of a PVA strand in centimeters, assuming that each monomer unit…

A: The O-C-C bond point in PVA chain is three-sided plannar, bringing about a bond point of 120°.…

Q: a_____ is a group of atoms bonded in a specific pattern and is the reactive portion of an organic…

A: Functional Group: A functional group is part of organic molecule is responsible for all chemical…

Q: 5) Below is a list of pros and cons to using aluminum cans vs. plastic bottles. Based on this list,…

A: The objective of the question is to discuss the effectiveness of material Based on the pros and cons…

Q: How can tungsten be conserved if it accidentally becomes contaminated?

A: Allowing the tungsten to touch the weld pool is one of the most common causes of contamination. This…

Q: Which is NOT true about diamonds? a. Diamonds are stable even under extremely hot temperatures. O b.…

A: The explanation is given below-