Chemistry

The observation that 4.0 g of hydrogen reacts with 32.0 g of oxygen to form a product with O:H mass ratio-8:1, and 6.0 g of hydrogen reacts with 48.0 g of oxygen to form the same product with O/H mass ratio = 8:1 is evidence for the law of 1. multiple proportions 2. erergy conservation. 3. mass conservation 4. definite proportion
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Which option correctly describes the enthalpy of formation?
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Why are relative atomic masses on the periodic tables not whole numbers?
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Predict the gravitational and electrostatic forces between molecules of gases? Provide evidence for your prediction.
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A sample of N2 gas is collected over water at 20o C and pressure of 1 atm. The volume collected is 250 Liters. What mass of N2 is collected?
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Write the rate law for the reaction 2A + B C if the reaction (1) is second order in B and overall third order, rA = ______ (2) is zero order in A and first order in B, rA = ______ (3) is zero order in both A and B, rA = ______ (4) is first order in A and overall zero order. rA = ______
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How can I lucid dream?
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A 1.00-kg block of copper at 100C is placed in an in- sulated calorimeter of negligible heat capacity containing 4.00 L of liquid water at 0.0C. Find the entropy change of (a) the cop- per block, (b) the water, and (c) the universe.
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Draw a structure containing only carbon and hydrogen that is a stable alkyne of five carbons containing a ring.
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Given a unsorted list of 1024 elements, what is the runtime for linear search if the search key is less than all elements in the list?
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Consider the second-order reaction: 2HI(g)H2(g)+I2(g). Use the simulation to find the initial concentration [HI]0and the rate constant k for the reaction. What will be the concentration of HI after t = 1.0110^10 s ([HI]t) for a reaction starting under the condition in the simulation?
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Potassium (K) has a work function value of 2.29 eV. What is the wavelength of light required to begin to generate a current in an apparatus like the one Hertz used with potassium metal?
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If 75 gm's of codeine phosphate is dissolved in 1.5 liters of sterile water, what is the resultant percentage strength of the solution?
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Which of the following would be expected to have the lowest freezing point? a. 0.1 M NaCl b. 0.1 M MgCl2 c. 0.1 M AlCl3
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If the pH of a solution is 5.3, what is the pOH?A.5.3B.4.7C.8.7D.9.3
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How many atoms of hydrogen are represented in 2(NH4)2504?A.4 B.8C.16D.32
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Could someone explain what oxidation numbers are and what these questions are asking of me?
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Consider a gas mixture in a 2.00-dm3 flask at 27.0 C. For each of the following mixtures, calculate the partial pressure of each gas, the total pressure, and the composition of the mixture in mole percent. a) 1.00 g H2 and 1.00 g O2 b) 1.00 g N2 and 1.00 g O2 c) 1.00 g CH4 and 1.00 g NH3
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What is the molarity of a 10.5 %% by mass glucose (C6H12O6C6H12O6) solution? (The density of the solution is 1.03 g/mLg/mL .) Express your answer to three significant figures.
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In the construction industry, why are I beams generally used as support as opposed to solid rectangular beams? What might be an advantage of using a rectangular beam?
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Two moles of nitrogen are initially at 10 bar and 600 K (state 1) in a horizontal piston/cylinder device. They are expanded adiabatically to 1 bar (state 2). They are then heated at constant volume to 600 K (state 3). Finally, they are isothermally returned to state 1. Assume that N 2 is an ideal gas with a constant heat capacity as given on the back flap of the book. Neglect the heat capacity of the piston/cylinder device. Suppose that heat can be supplied or rejected as illustrated below. Assume each step of the process is reversible. Calculate the net work done overall.
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What is the name for NH
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The density of air under ordinary conditions at 25 degrees * C is 1.19g / L . How many kilograms of air are in a room that measures 9.0ft * 11.0ft and has a 10.0 ft ceiling?
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An element has four naturally occurring isotopes with the masses and natural abundances given in the table below. Find the atomic mass of the element (express your answer to four significant figures and include the appropriate units). Isotope Mass (amu) Abundance (%) 1 203.97304 1.390 2 205.97447 24.11 3 206.97590 22.09 4 207.97665 52.41 Identify the element, by spelling out its full name.
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