Answer:
345J
Explanation:
-mass of iron (m) = 10.0 g
-temperature (ΔT) = final temperature- initial temperature= 100-25= 75 degree Celsius
-Specific Heat capacity of iron (c)= 0.46J/g°C.
Heat (Q)=?
Solution:
Formula for Heat is :
Q=m x c x ΔT
Q= 10 x 0.46 x 75
Q= 345 J.
so, 345 joules of heat are needed to increase the temperature of 10 grams of iron.
From the above formula, all other questions can easily be solved from the same procedure.
Answer:
N2+O2-> 2NO
Explanation:
An endothermic reaction refers to a reaction in which heat taken in. This implies that heat is usually absorbed by the reaction system. The enthalpy of reaction for an endothermic reaction is always positive.
The triple bond between two Nitrogen atoms in N2 gas is very strong due to its small size and the triple bond thus the nitrogen molecule has a high dissociation energy. This accounts for the large amount of energy required to break the triple bond between nitrogen atoms in the nitrogen molecule. This causes the oxidation of Nitrogen molecule to NO to be largely endothermic.
Data:
<span>Solute: 28.5 g of glycerin (C3H8O3)
Solvent: 135 g of water at 343 k.
Vapor pressure of water at 343 k: 233.7 torr.
Quesiton: Vapor pressure of water
Solution:
Raoult's Law: </span><span><span>The vapour
pressure of a solution of a non-volatile solute is equal to the vapour
pressure of the pure solvent at that temperature multiplied by its mole
fraction.
Formula: p = Xsolvent * P pure solvent
X solvent = moles solvent / moles of solution
molar mass of H2O = 2*1.0g/mol + 16.0 g/mol = 18.0 g/mol
moles of solvent = 135 g of water / 18.0 g/mol = 7.50 mol
molar mass of C3H8O3 = 3*12.0 g/mol + 8*1 g/mol + 3*16g/mol = 92 g/mol
moles of solute = 28.5 g / 92.0 g/mol = 0.310 mol
moles of solution = moles of solute + moles of solvent = 7.50mol + 0.310mol = 7.810 mol
Xsolvent = 7.50mol / 7.81mol = 0.960
p = 233.7 torr * 0.960 = 224.4 torr
Answer: 224.4 torr
</span> </span>
At the physically impossible-to-reach temperature of zero<span> kelvin, or minus 459.67 degrees Fahrenheit (minus 273.15 degrees Celsius), atoms would stop moving. As such, nothing can be colder than </span>absolute zero<span> on the Kelvin scale</span>