Explanation:
We have to find the number of moles of N₂ that are present in a sample that has a volume of 40.0 L at STP.
STP means Standard Conditions of Temperature and Pressure. These conditions are 273.15 K and 1 atm. We know that 1 mol of N₂ will occupy 22.4 L. We can use that ratio to find the answer to our problem.
1 mol of N₂ = 22.4 L
moles of N₂ = 40.0 L * 1 mol/(22.4 L)
moles of N₂ = 1.79 mol
Answer: 1.79 moles of nitrogen are present.
Pure substance element I think
Use the nernst equation : <span><span>E<span>cell</span></span>=E−<span><span>RT</span><span>nF</span></span>ln<span><span>[F<span>e<span>3+</span><span>out</span></span>]</span><span>[F<span>e<span>3+</span><span>in</span></span>]</span></span></span>
At eq. <span>ΔG=0=−nF<span>E<span>cell</span></span>→<span>E<span>cell</span></span>=0</span>
and thus: <span>E=<span><span>RT</span><span>nF</span></span>ln<span><span>[F<span>e<span>3+</span><span>out</span></span>]</span><span>[F<span>e<span>3+</span><span>in</span></span>]</span></span></span>
Answer:
The heat needed to warm 25.3 g of copper from 22°C to 39°C is 165.59 Joules.
Explanation:
Where:
Q = heat absorbed or heat lost
c = specific heat of substance
m = Mass of the substance
ΔT = change in temperature of the substance
We have mass of copper = m = 25.3 g
Specific heat of copper = c = 0.385 J/g°C
ΔT = 39°C - 22°C = 17°C
Heat absorbed by the copper :
The heat needed to warm 25.3 g of copper from 22°C to 39°C is 165.59 Joules.
Krypton- rare gas, element in the noble gases
Lye- sodium hydroxide, compound
Graphite- element
Vinegar- is acetic acid, compound( aqueous solution)