A hot plate, a large beaker of water, and grains of rice are used in a class demonstration. When the water begins to boil, the rice moves in a circular pattern. The model demonstrates

What mass of natural gas (ch4) must you burn to emit 276 kj of heat?

An alloy contains 66 g of pure zinc. what is the percentage of zinc in the alloy? express your answer to two significant figures and include the appropriate units.

Achemist who studies water samples did a demonstration of how to test for lead in water. she added a clear solution of potassium iodide to a clear solution of lead nitrate. then a yellow swirling solid formed in the liquid. what is most likely true about the yellow solid?