Mass (g) before burning Mass (g) after burning
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While studying chemical reactions and conservation of matter, Sarah's class conducted a variety of experiments. Sarah and her lab partner found the mass of a wax candle and placed the candle in a flask. The students lit the candle and let it burn to completion. All that was left was wax and charred candle wick. Per their teacher's instructions, the students found the mass of the products. Their data can be seen in the data table. Formulate a hypothesis the students could test to explain why the experiment did not support the law of conservation of matter.
A) The students could repeat the experiment using different candles; there might have been a flaw in the candle.
B) The experiment should be repeatable. The students should run several trials and then take an average of the after mass in each trial.
C) The students should have someone in the class check their measurement skills as they repeat the experiment. They may have made an error using the balance.
D) The students should burn the candle in a container that has some type of lid so that any gas that is a product of the reaction can be contained and massed.

Determine the energy released per kilogram of fuel used. given mev per reaction, calculate energy in joules per kilogram of reactants. consider 1 mole of tritium plus 1 mole of deuterium to be a mole of “reactions” (total molar mass = 5 grams).

1. calculate the approximate enthalpy of the reaction in joules. estimate that 1.0 ml of vinegar has the same thermal mass as 1.0 ml of water. iqnore the thermal mass of th sodium bicarbonate. note: it takes about 4.2 joules () to change 1.0 gram (1.0ml) of water 1.0 c

Nconcentration refers to the molar concentration of an ion in solution. it may be identical to, or greater or less than, the molar concentration of the compound containing the ion that was used to make the solution. for soluble salts, the molarity of a particular ion is equal to the molarity of that compound times the subscript for that ion. for example, 1 m of alcl3 is 1 m in al3+ and 3 m in cl−. 1 m of (nh4)2so4 is 2 m in nh4+ and 1 m in so42−. part a what is the concentration of k+ in 0.15 m of k2s? view available hint(s) nothing m m part b if cacl2 is dissolved in water, what can be said about the concentration of the ca2+ ion? view available hint(s) if is dissolved in water, what can be said about the concentration of the ion? it has the same concentration as the cl− ion. its concentration is half that of the cl− ion. its concentration is twice that of the cl− ion. its concentration is one-third that of the cl− ion. part c a scientist wants to make a solution of tribasic sodium phosphate, na3po4, for a laboratory experiment. how many grams of na3po4 will be needed to produce 550 ml of a solution that has a concentration of na+ ions of 0.700 m ? express your answer numerically in grams. view available hint(s) mass of na3po4 n a 3 p o 4 = nothing g provide feedback