Chemistry

What common household element can, over time, reduce airflow, insulate components, reduce heat exchange or even cause the system to hang or reboot?
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Drinking after running on a hot day replaces water lost through
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In the simulation, open the Micro mode, then select the solutions indicated below from the dropdown list above the beaker. The beaker will fill up to the 0.50 L mark with the solution. Arrange the solutions in increasing order of basicity.drain cleaner, hand soap, blood, milk, orange juice, soda pop
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Calculate the molalities of some commerical reagents from thefollowing data:HCl has a formula weight (amu) of 36.465, Density of thesolution(g/mL) of 1.19, Weight % of 37.2, and Molarity of12.1.HC2H3O2 has a formula weightof 60.05, Density of 1.05, Weight % of 99.8, and Molarity of17.4.NH3(aq) has a formula weight of 17.03, Denisty of0.90, Weight % of 28.0, and Molarity of 14.8
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At high temperatures phosphine (PH_3) dissociates into phosphorus and hydrogen by the following reaction: 4PH3 rightarrow P_4 + 6H_2 At 800 degree C the rate at which phosphine dissociates is dC_PH_3/dt = -3.715 times 10^-6 C_PH_3. for t in seconds. The reaction occurs in a constant-volume, 2-L vessel, and the initial concentration of phosphine is 5kmol/m^3 a. If 3mol of the phosphine reacts, how much phosphorus and hydrogen is produced? b. Develop expressions for the number of moles of phosphine, phosphorus, and hydrogen present at any time, and determine how long it would take for 3 mol of phosphine to have reacted.
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A compound that would be most soluble in water would be: a. glucose b. cholesterol. c. a large protein. d. a triglyceride.
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Which of the following should most favor the solubility of an ionic solid in the water? Note: high and low refers to the magnitudes (i.e. the absolute value) of lattice and hydration energies. Select one: A) a low lattice energy for the solid and a low hydration energy for its ions B) low lattice energy for the solid and a high hydration energy for its ions C) a high lattice energy for the solid and a low hydration energy for its ions D) a high lattice energy for the solid and a high hydration energy for its ions
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How much heat (in joules) is required to raise the temperature of 30.0 kg of water from 15o C to 95o C?
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Make a drawing of the particles in an NaCl solution to show why this solution conducts electricity. Make a drawing of the particles in an NaCl crystal to show why pure salt does not conduct.
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How can chemical weathering contribute to physical weathering?A-leads to the abrasion of rocks and mineralsB-increases the surface exposed to the atmosphereC-increases the temperature of rocks and soilsD-decreases the amount of biological activity acting on a rockUnder which of the following conditions would chemical weathering rates be highest?A-dense vegetation coverB-large grain sizeC-rocks made predominantly of silicate mineralsD-constant cold temperaturesBuildings and statues made of stone are subject to the same degree of weathering as rocks in the natural environment.True or false?
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the pressure on a gas at -73 C is doubled but its volume is held constant. what will the final temperature in degrees be?
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100. mg of an unknown protein are dissolved in enough solvent to make 5.00mL of solution. The osmotic pressure of this solution is measured to be 0.0766 atm at 25.0 degree C . Calculate the molar mass of the protein. Be sure your answer has the correct number of significant digits.
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Question 7 of an unknown protein are dissolved in enough solvent to make of solution. The osmotic pressure of this solution is measured to be at . Calculate the molar mass of the protein. Round your answer to significant digits.
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. The order of a chemical reaction with respect to one of its reactants is 0. If you double the concentration of that reactant, the reaction rate will _______. A. be cut in half B. double C. increase by an undetermined amount D. remain unchanged E. None of the Abov
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We drop a cube of ice into a glass of water. The mass of the cube of ice is 33.1 g and its initial temperature is 10.2C. The mass of the water is 251 g and its initial temperature is 19.7C. What is the final temperature of the water after all of the ice has melted?
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Select the correct answer from each drop-down menu.Complete the statements about the nature of scientific knowledge.Among the different types of scientific knowledge, are likely to be modified or discarded most frequently. Long ago, in the 1600s, scientists discarded the phlogiston theory because
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Membrane Conductance You are doing a measurement to determine the conductance of an artificial membrane. The membrane is selectively permeable to Na . The temperature is 15 degrees C The external concentrate of Na is 500 mM The internal concentration of Na is 70 mM Using a voltage clamp apparatus you clamp the membrane voltage (Vm) at 20 mV At this clamped voltage you measure a current of -318 nA What is the membrane's conductance
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Molybdenum (Mo) has a body centered cubic unit cell. The density of Mo is 10.28 g/cm3. Determine (a) the edge length of the unit cell and (b) the radius of a Mo atom.
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I have made 15 ml of 200 mM CaCl2 stock and need to make 40 ml of 50mM for my experiment. How much of my concentrated stock solution (in milliliters) and how much water do I need to mix to make the 40 ml of 50mM CaCl2 ?
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Which functional group is not found in gingerol [pictured below], the flavor component of fresh ginger?Group of answer choicesaldehydeketoneetheralcoholaromatic ring
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TV and radio stations transmit in specific frequency bands of the radio region of the electromagnetic spectrum.(a) TV channels 2 to 13 (VHF) broadcast signals between the frequencies of 59.5 and 215.8 MHz, whereas FM radio stations broadcast signals with wavelengths between 2.78 and 3.41 m. Do these bands of signals overlap?(b) AM radio signals have frequencies between 550 and 1600 kHz. Which has a broader transmission band, AM or FM?
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How does William Jennings Bryan respond to the criticism that the free and unlimited coinage of silver will disrupt ""business interests""?
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Which of the following changes to a pipe would increase the conductance by a factor of 12? A. Quadrupling the length and tripling the radius. B. Reducing the length by a factor of and doubling the radius. C. Tripling the length and reducing the radius by a factor of . D. Reducing the length but a factor of and doubling the radius.
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Consider the following three molecules: pentanal 3-pentanone 1,3,5-pentanetriol [pictured]Which statement is correct?Group of answer choicesall three molecules have five carbonsone of the three molecules has a carbonyl groupall three molecules are derived from pentyneall three molecules have the same number of hydrogensall are soluble in organic solvents
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