Here are the data obtained by one pair of students when they performed the experiment on the density of a gas: Mass of test tube, water, and tablet before the reaction 35.00 g
Mass of test tube and contents after the reaction 34.22 g
Volume of gas collected 411 cm3

Which method should the students use to calculate the density of the gas in g/cm3?

A. 35.00
411

B. 34.22
411

C. 411
35.00

D. 411
35.00-34.22

E. 35.00-34.22
411

Why cooking gas has a typical smell

Use the right-hand rule for magnetic force to determine the charge on the moving particle. this is a charge.

Aheat engine running backward is called a refrigerator if its purpose is to extract heat from a cold reservoir. the same engine running backward is called a heat pump if its purpose is to exhaust warm air into the hot reservoir. heat pumps are widely used for home heating. you can think of a heat pump as a refrigerator that is cooling the already cold outdoors and, with its exhaust heat qh, warming the indoors. perhaps this seems a little silly, but consider the following. electricity can be directly used to heat a home by passing an electric current through a heating coil. this is a direct, 100% conversion of work to heat. that is, 19.0 \rm kw of electric power (generated by doing work at the rate 19.0 kj/s at the power plant) produces heat energy inside the home at a rate of 19.0 kj/s. suppose that the neighbor's home has a heat pump with a coefficient of performance of 4.00, a realistic value. note: with a refrigerator, "what you get" is heat removed. but with a heat pump, "what you get" is heat delivered. so the coefficient of performance of a heat pump is k=qh/win. an average price for electricity is about 40 mj per dollar. a furnace or heat pump will run typically 200 hours per month during the winter. what does one month's heating cost in the home with a 16.0 kw electric heater? what does one month's heating cost in the home of a neighbor who uses a heat pump to provide the same amount of heating?