How many significant figures are in 0.0810300600 kg

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.

An experimental procedure requires a 10 ml of acid to be dissolved

In a reaction (at equilibrium) that makes more moles of gas than it consumes, what is the effect of increasing the pressure?