Answer:
Mass of 1 mole of copper is 63.83 g.
0.03916 moles of copper atoms have a mass equal to the 2.5 grams of copper penny.
Explanation:
Mass of 1 copper atom,m = 

Mass of 1 mole of copper :
= 
Mass of 1 mole of copper = 63.83 g
Mass of copper penny = 2.5 g
Atomic mass of copper = 63.83 g/mol
Moles of copper in 2.5 g of copper penny:

0.03916 moles of copper atoms have a mass equal to the 2.5 grams of copper penny.
Answer:
Dinitrogen tetroxide, commonly referred to as nitrogen tetroxide (NTO), and occasionally (usually among ex-USSR/Russia rocket engineers) as amyl, is the chemical compound N2O4.
Answer: The temperature of 0.6 moles of fluorine that occupy 15 L at 2,300 mmHg is 920 K
Explanation:
According to ideal gas equation:

P = pressure of gas = 2300 mm Hg = 3.02 atm (760mmHg=1atm)
V = Volume of gas = 15 L
n = number of moles = 0.6
R = gas constant =
T =temperature = ?


Thus the temperature of 0.6 moles of fluorine that occupy 15 L at 2,300 mmHg is 920 K
Answer:
Carbon dioxide reacts with limewater (a solution of calcium hydroxide, Ca(OH) 2), to form a white precipitate (appears milky) of calcium carbonate, CaCO 3.
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