June 2019 Chemistry Regents #66-69
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During a laboratory
activity, appropriate safety equipment was used and safety procedures
were followed. A laboratory technician heated a sample of solid KClO3
in a crucible to determine the percent composition by mass of
oxygen in the compound. The unbalanced equation and the data for
the decomposition of solid KClO3 are shown below.
66.Write the chemical name for the compound that
Answer--> potassium chlorate|
67. Based on the lab data, show a numerical setup to
determine the number of moles of O2 produced. Use
32g/mol as the gram-formula mass of O2.
just the setup|
68. Based on the lab data, determine the mass
of KCl produced in the reaction.
69. Balance the equation in the
Answer--> 2KClO3 --> 2 KCl
+ 3 O2|
see Table F halides