At the start of the coal combustion experiment, the combined mass of the coal and oxygen reactants was 100 grams. At the end of the coal combustion experiment, the mass of the sample was 100 grams. Why does the scale showing the mass at the end of the reaction give a mass of 100 grams, when there is only a small amount of solid particles remaining on the scale?

Which of these will change if the air in aclosed bottle is heated? abcdthe mass of the airthe composition of the airthe air pressure in the bottlethe number of air molecules in the bottle

Explain in detail of the four major scientific developments that spurred the formulation of the plate tectonics theory

Consider a culture medium on which only gram-positive organisms such as staphylococcus aureus colonies can grow due to an elevated nacl level. a yellow halo surrounds the growth, indicating the bacterium fermented a sugar in the medium, decreasing the ph as a result and changing the color of a ph indicator chemical. this type of medium would be referred to as a differential and enrichment culture.