Answer. Statement second and third both are correct.
Explanation: When iron(grey) reacts with sulfur(yellow) chemical change takes place in which iron sulfide is formed which black in color.
When we heat copper sulfate-pentahydrate(blue) ,water molecule present in its crystal will get evaporated and it will become an anhydrous copper sulfate which will be white in color.
So, in both the reactions change in color and change in chemical arrangement has taken place.
Answer : To calculate the standard molar enthalpy of complete combustion of liquid ethanol can be done by using the formula given below;
Now, the enthalpies of the elements in their standard state is zero always.
So the
Here we can avoid the heat of enthalpy of oxygen,carbon dioxide and water as they exists in their standard states.
So the
=
1. exercise because you are using exercise to affect the amount of concentration. 2. concentration because concentration is what is being measured
The temperature in kelvin does 60.5 liters of sulfur dioxide occupy if there are 2.5 mole at 0.75 atm is 221.07 kelvin
Explanation
This is calculated using ideal gas equation, that is PV=nRT
where, P(pressure) = 0.75 atm
V(volume) = 60.5 L
n(moles) = 2.5 mole
R( gas constant) = 0.0821 L.atm/mol.k
T(temperature =?
by making T the subject of the formula
T is therefore =Pv/nR
T= (0.75 atm x 60.5 L) / ( 2.5 molex 0.0821 L.atm/mol.K) = 221.07 kelvins
Answer: Crescent
Explanation: Image result for In what phase is the moon if it is gaining light and less than half illuminated
Crescent Moons are when it's less than half illuminated, and gibbous when it's more than half. “Waxing” means that the Moon becomes more illuminated night-by-night, and the term “waning” means that it's getting less illuminated each night.
