June 2015 Chemistry Regents #21-25
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Questions | Answer | Links | Explanations |
21. In a redox reaction, which particles are lost and gained in equal numbers? (1) electrons (3) hydroxide ions (2) neutrons (4) hydronium ions | 1 | Link | Reduction-oxidation (redox) reactions are chemical reactions in which reactants experience a change in oxidation number (which means these reactants either gain or lose electrons). |
22. What is the oxidation state for a Mn atom? (1) 0 (2) +7 (3) +3 (4) +4 | 1 | link | free elements have an oxidation state of zero also atoms have no charge |
23. Which compounds are classified as electrolytes? (1) KNO3 and H2SO4 (2) KNO3 and CH3OH (3) CH3OCH3 and H2SO4 (4) CH3OCH3 and CH3OH | 1 | link | acids bases and soluble salts |
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24. Which compound is an Arrhenius base? (1) CO2 (2) CaSO4 (3) Ca(OH)2 (4) C2H5OH | 3 | link | bases have hydroxide in the formula exclude alcohols |
25. According to one acid-base theory, a water molecule acts as a base when it accepts (1) an H+ ion (3) a neutron (2) an OH- ion (4) an electron | 1 | link | acid: anything that donates a [H+] (proton donor) base: anything that accepts a [H+] (proton acceptor) |
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