Que cambios son fisicos y cuales son quimicos? ?
a) quemar papel
b) limpiar objetos de plata
c) hacer hielo en el congelador
d) fundir hierro

In a laboratory experiment, a fermenting aqueous solution of glucose and yeast produces carbon dioxide gas and ethanol. the solution was heated by burning natural gas in a bunsen burner to distill the ethanol that formed in the flask. during the distillation, the ethanol evaporated and then condensed in the receiving flask. the flame of the burner was kept too close to the bottom of the flask and some of the glucose decomposed into a black carbon deposit on the inside of the flask. during this experiment the following changes occurred. which of these changes involved a physical change and not a chemical change? check all that apply. 1-condensation of ethanol 2-evaporation of ethanol 3- formation of carbon dioxide gas from glucose burning of natural gas 4-formation of ethanol from glucose by yeast 5-formation of a carbon deposit inside the flask

Pbco3 –> pbo+ co2. how many liters of carbon dioxide gas is produced from the decomposition of 32 grams of lead (ll) carbonate?

If 1.8 l of water is added to 2.5l of a 7.0 m koh solution, what is the molarity of the new solution