Answer:
egg: endothermic
candle: exothermic
plaster and water : exothermic
salt and water: neither
The early atmosphere of the earth would consist of gases like nitrogen and carbon dioxide and about 2.5 billion years ago oxygen started to form and some of these gases would have been expelled by volcanoes and also the atmosphere would stay close to the surface of the earth due to gravity that held it there.
I would say D. Let me know if i am wrong.
Answer:
126g
Explanation:
Data obtained from the question include:
Mole of Fe = 2.5moles
Molar Mass of Fe = 56g/mol
Mass of Fe =?
Number of mole = Mass/Molar Mass
Mass = number of mole x molar Mass
Mass of Fe = 2.25 x 56
Mass of Fe = 126g
Therefore, the mass in 2.25mol of Fe is 126g