<span>If both samples decompose when heated they cannot be elements, because elements don't decompose. As a matter of fact that is one of the definitions of an element--a substance that cannot be broken down into anything simpler by chemical methods.
Compounds that are the same have the same chemical and physical properties, so if one of the compounds is soluble in water, then both are soluble in water.
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two different compounds.</span>
Answer:
20.2 kJ
Explanation:
Based on the information in the reaction, the amount of heat released per mole of Na₂O₂ (the molar enthalpy) is calculated as follows:
126 kJ / 2 mol = 63 kJ/mol Na₂O₂
The number of moles in 25.0g of Na₂O₂ must be calculated using the molecular weight of Na₂O₂ (77.978 g/mol):
(25.0 g)/(77.978 g/mol) = 0.32060 mol Na₂O₂
Thus, the heat released will be:
(63 kJ/mol)(0.32060 mol) = 20.2 kJ
Answer: This is the hue of mercury if you're looking for it. Mercury reacts with sulphur to generate a crimson hue. In the past, they always used a thermometer.
Explanation: However, due of its toxicity, individuals have switched to using alcohol in glass thermometers, which work similarly to mercury thermometers.
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Her model allows Christina to gather data about wave P, since she created a model.