phosphine contains 91.1% of p and 8.9% of h, water contains 88.8% of o and 11.2% of h, phosphorus tetroxide contains 56.4% of p and 43.6% of o. show that these data illustrate the law of reciprocal proportion.

The density of a planet is 0.69 g/cm3 (density of water is 1.0 g/cm3). which of the following planets might this be? a. mercury b. venus c. saturn d. mars

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Which of these would be caused by a chemical change? a) the formation of lava. b) sedimantary rock layering over time. c) metamorphic rock forming from igneous. d) metamorphic rock eroding to form sedimentary rock.