Which of the following reactions shows a chemical change producing a gas? O A. 2CH2OH() + 302(9) ► 2002(9) + 4H20 (1)
B. 2AgNO3(aq) + CaBr2(aq) → 2AgBr(s) + Ca(NO3)2(aq)
C. NaCl(s) - NaCl(aq)
O D. H2(g) + O2(g) → H20(1)

An alkaline battery produces electrical energy according to the following equation. zn(s) + 2 mno2(s) + h2o(l) zn(oh)2(s) + mn2o3(s) (a) determine the limiting reactant if 17.5 g zn and 31.0 g mno2 are used. (type your answer using the format ch4 for ch4.) (b) determine the mass of zn(oh)2 produced. _ g

Once similarity and one difference between a mixture of elements and a mixture of compounds

A0.10 m aqueous solution of sodium sulfate is a better conductor of electricity than a 0.10 m aqueous solution of sodium chloride. which of the following best explains this observation? (a) sodium sulfate is more soluble in water than sodium chloride. (b) sodium sulfate has a higher molar mass than sodium chloride. (c) to prepare a given volume of 0.10 m solution, the mass of sodium sulfate needed is more than twice the mass of sodium chloride needed. (d) more moles of ions are present in a given volume of 0.10 m sodium sulfate than in the same volume of 0.10 m sodium chloride. (e) the degree of dissociation of sodium sulfate in solution is significantly greater than that of sodium chloride.