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4. A sample of iron ore is 35% pure iron. If 5.34 kg of iron ore is mined, how many moles of pure iron are present? (3 pts)

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

How are isotopes of the same chemical element alike? how are they different?

Which organism develops breathing organism develops breathing organs from pharyngeal arches? shark, spider, sea star, sea horse