Which scientist is known for developing the planetary model of the atom? Niels Bohr Albert Einstein Johannes Rydberg Robert Millikan
What was the robotic vehicle Opportunity designed to do? A. probe beneath the moon’s surface for signs of volcanic activity B .map the contours of craters and valleys on the moon C. determine the chemical composition of rocks and soil on Mars D. measure precipitation on Mars
Nitrogen and hydrogen combine at high temperature, in the presence of a catalyst, to produce ammonia. . N2(g)+3H2(g)=2NH3(g). . Assume 0.280 mol of N2 and 0.884 mol of H2 are present initially.. . After complete reaction, how many moles of ammonia are produced?__________. . How many moles of H2 remain?___________. . How many moles of N2, remain?___________. What is the limiting reactant?________(nitrogen or hydrogen)
The reaction below has an equilibrium constant kp=2.2×106 at 298 k. 2cof2(g)⇌co2(g)+cf4(g) calculate kp for the reaction below. cof2(g)⇌12co2(g)+12cf4(g)
Which statement about gases is true? A.They are made up of particles that always move very slowly. B.They are made up of particles that travel in a curved path when in motion. C.They are made up of hard spheres that vibrate quickly in stationary positions. D.They are made up of hard spheres that are in random motion.
What is the best description of what Becquerel observed in his experiment? A.stable nuclei absorbing high-energy particles as they formed less stable compositions B.stable nuclei emitting high-energy particles as they formed less stable compositions C.unstable nuclei absorbing high-energy particles as they formed more stable compositions D.unstable nuclei emitting high-energy particles as they formed more stable compositions
Question 15 at what stage of a reaction do atoms have the highest energy? reactant stage product stage transition state stage the stage of highest energy depends on the atom.
Which best describes a swimming pool? 1.) it is a solute 2.) it is a solvent 3.) it is a solution 4.) it is a reactant 5.) it is a product
How do the products and reactants of a chemical change compare? The mass of the products is greater than the mass of the reactants because energy is taken in by the reaction. The mass of the products equals the mass of the reactants because the same matter is present. The mass of the products equals the mass of the reactants because there is no energy involved in the reaction. The mass of the products is less than the mass of the reactants because energy is given off by the reaction.
Determine the empirical formula for a compound that is 36.86% n and 63.14% o by mass. determine the empirical formula for a compound that is 36.86% n and 63.14% o by mass. no
Detergent has a ph of about 10. is detergent acidic or basic? use figure 8-3 to answer this question.
With solutions of strong acids and strong bases, the word strong refer to ____. (1 point) normality molarity solubility degree of ionization
What is the salt produced when sulfuric acid (H2SO4) reacts with potassium hydroxide (KOH)?a)SO4Kb)K2SO4c)KSO4d)H2O
What is the empirical formula of ascorbic acid, given that the pseudoformula is c3.407h4.53o3.406? express your answer as a chemical formula?
For an aqueous solution of hf, determine the van't hoff factor assuming 0% and 100% ionization, respectively. a solution is made by dissolving 0.0100 mol hf in enough water to make 1.00 l of solution. at 22 Â°c, the osmotic pressure of the solution is 0.307 atm. what is the percent ionization of this acid?
Which of these solutions has the lowest freezing point? 0.25 m nacl 0.5 m nacl 1.0 m nacl 1.5 m nacl 2.0 m nacl
Which sample, when dissolved in 1.0 liter of water, produces a solution with the highest boiling point?
Which of the following is not an example of a physical property? a. freezing point c. reactivity b. boiling point d. density
Which statement correctly explains the polarity of the water molecule? A. The hydrogen end of the molecule has a partial negative charge and the oxygen end has a partial positive charge. B. The oxygen end of the molecule has a partial negative charge and the hydrogen end has a partial positive charge. C. Both ends of the molecule have a partial negative charge, which attracts the other water molecule towards itself.
Based on the sign of E cell, classify these reactions as spontaneous or non spontaneous as written.? assume standard conditions. Ni^2+ (aq) + S^2- (aq) ----> + Ni (s) S (s) (nonspontaneous)? Pb^2+ (aq) +H2 (g) ----> Pb (s) +2H^+ (aq) (nonspontaneous)? 2Ag^+ (aq) + Cr(s) ---> 2 Ag (s) +Cr^2+ (aq) (spontaneous?) Are these correct?
Which of the following statements describes a scientific law? a. A scientific law explains a set of events. b. A scientific law describes what occurs every time in a situation. c. A scientific law is constantly modified. d. A scientific law is developed without experimentation.
What should the IUPAC name for a binary covalent compound lack? prefixes Roman numerals an -ide ending the name of a nonmetal