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In eukaryotes, an activator binds to what type of regulatory sequence?

A lab assistance prepares 2.50 liters of a 0.5000 M KCl solution.  What mass of KCl was used to prepare this particular solution? (Molar masses of K = 39.098 g/mol, Cl = 35.45 g/mol)  — [HINT: How is “M” defined?]

By what mechanism does a catalyst increase the rate of a reaction?  The image below should be helpful.

What are valence electrons and how is valence electron count depicted on the periodic table for a given group?

Which of the following chemical equations (numbered 1 – 3) depict a weak acid? Reaction 1: HCl → H+ (aq) + Cl− (aq) Reaction 2: HC2H3O2 ⇌ H+ (aq) + C2H3O2− (aq) Reaction 3: NH3(aq) + H + (aq) ⇌ NH4 + (aq) [Hint: Firstly, how do you identify a compound as an acid?]

Convert 36.0 cubic centimeters (cm3) to cubic inches (in3).  Note, there are 2.54 cm per inch.  [HINT: Did your units cancel correctly?]

What is the pH of a 2.5 M solution of acetic acid at equilibrium? (Balanced eq: HC2H3O2(aq) + H2O(l) + ⇌ H3O+(aq) + C2H3O2−(aq);  Ka of HC2H3O2 is 1.8 × 10−5 [Hint: What is the definition of pH?]

A 44.5 liter gas cylinder is filled with oxygen gas (O2) at a pressure of 2.00 atm and temperature of 25.00 Celsius.  Calculate the mass (in grams) of oxygen gas in the cylinder under these conditions (Molar mass of oxygen = 16.00 grams/mol; R = 0.08206 (L x atm)/(mol x K); conversion of Celsius to Kelvin: C + 273.15 = K)  — [HINTS: PV=nRT; Did your units cancel to give the requested unit?]

Which collision factor benefits the most directly from heating a reaction mixture?

Would you expect the following compound to be polar?